Field Book for Describing and Sampling Soils

Field Book
for Describing and
Sampling Soils
Version 1.1
Revised, Refined, and Compiled by:
P.J. Schoeneberger, D.A. Wysocki,
E.C. Benham, and W.D. Broderson
National Soil Survey Center
Natural Resources Conservation Service
U.S. Department of Agriculture
Lincoln, Nebraska
The science and knowledge in this document are distilled from the collective
experience of thousands of dedicated Soil Scientists during the nearly
100 years of the National Cooperative Soil Survey Program. A special
thanks is due to these largely unknown stewards of the natural resources of
this nation.
Special thanks and recognition are extended to those who contributed
extensively to the preparation and production of this book: The 75 soil
scientists from the NRCS along with NCSS cooperators who reviewed and
improved it; Tammy Nepple for document preparation and graphics; Howard
Camp for graphics; Jim Culver for sponsoring it; and the NRCS Soil Survey
Division for funding it.
Proper citation for this document is:
Schoeneberger, P.J., Wysocki, D.A., Benham, E.C., and Broderson,
W.D. 1998. Field book for describing and sampling soils. Natural
Resources Conservation Service, USDA, National Soil Survey Center,
Lincoln, NE.
Cover Photo: Soil profile of a Segno fine sandy loam (Plinthic Paleudalf)
showing reticulate masses or blocks of plinthite at 30 inches (profile tape is
in feet). Courtesy of Frankie F. Wheeler, NRCS, Temple TX; and
Larry Ratliff (retired), National Soil Survey Center, Lincoln, NE.
Use of trade or firm names is for reader information only, and does not constitute
endorsement or recommended use by the U.S. Department of Agriculture of any
commercial product or service.
The United States Department of Agriculture (USDA) prohibits discrimination in its
programs on the basis of race, color, national origin, sex, religion, age, disability,
political beliefs, and marital or familial status. (Not all prohibited bases apply to all
programs.) Persons with disabilities who require alternative means for
communication of program information (Braille, large print, audiotape, etc.) should
contact USDA's TARGET Center at 202-720-2600 (voice and TDD).
To file a complaint of discrimination, write USDA, Director, Office of Civil Rights,
Room 326-W, Whitten Building, 14th and Independence Avenue, SW, Washington,
DC 20250-9410 or call (202) 720-5964 (voice or TDD). USDA is an equal
employment opportunity employer.
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Purpose: The following instructions, definitions, concepts, and codes are a
field guide for making or reading soil descriptions and sampling soils as
presently practiced in the USA.
Background: This document is an expanded and updated version of earlier
guides and short-hand notation released by the Soil Conservation
Service (e.g., Spartanburg, SC, 1961; Western Technical Center,
Portland, OR, 1974). The knowledge base in those releases was
developed by soil scientists during the formative years of the Soil
Survey Program. Roy Simonson and others summarized this
information in the 1950s (e.g., Soil Survey Staff, 1951; Soil Survey
Staff, 1962). This document summarizes our present knowledge base.
Standards: This book summarizes the current National Cooperative Soil
Survey conventions for describing soils. Where the content deviates
from the initial sources (SSM, 1993; NSSH, 1996; PDP 3.6, 1996; etc.),
excepting errors, this document updates them.
Regarding PEDON (PDP 3.5 / 3.6): This document is intended to be both
current and useable by the entire soil science community; it is not a
guide on “How to use the Pedon Description Program (PDP)”. At this
time, PDP is the most dated and therefore the least compatible NRCS
document relative to the Soil Survey Manual, National Soil Survey
Handbook, Keys to Soil Taxonomy, and NASIS. Differences and
linkages between PDP 3.6 and NASIS are shown, where reasonable to
do so, as an aid to conversions. Future releases of this book are
unlikely to include PDP materials.
Standard procedures and terms for describing soils have changed and
increased in recent years (e.g., redoximorphic features). Coincident
with these changes has been the development and use of computer
databases to store soil descriptions and information. The nature of
databases, for better or worse, requires consistent and “correct” use of
terms.
Sources: This Field Book draws from several primary sources: The Soil
Survey Manual (Soil Survey Staff, 1993); the PEDON Description
Program (PDP) Version 4 Design Documents (Soil Survey Staff,
1996d); and the National Soil Survey Handbook (NSSH) -- Parts 618
and 629 (Soil Survey Staff, 1996c). Other less pervasive sources are
footnoted throughout the Field Book to encourage access to original
information.
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Brevity: In a field book, brevity is efficiency. Despite this book’s apparent
length, the criteria, definitions, and concepts presented here are
condensed. We urge users to review the more comprehensive
information in the original sources to avoid errors due to our brevity.
Units: It is critical to specify and consistently use units for describing a soil.
Metric units are preferred. NASIS requires metric units. (In PDP, you
can choose Metric or English units.)
Format: The “Site Description Section” and “Profile Description Section” in
this book generally follow conventional profile description format and
sequence (e.g., SCS-232, December 1984). Some data elements
(descriptors) are rearranged in this document into a sequence that is
more compatible with the description process in the field (e.g., Horizon
Boundary is next to Horizon Depth, rather than at the very end). This
sequence is somewhat different from and does not supersede the
conventions followed in writing formal soil descriptions for Soil Survey
Reports or Official Soil Series Descriptions (i.e., National Soil Survey
Handbook, Part 614, p. 13-22; Soil Survey Staff, 1996).
Codes: Short-hand notation is listed in the Code column for each descriptor.
Long-standing, conventional codes are retained because of their
widespread recognition. Some codes of recent origin have been
changed to make them more logical. Some data elements have
different codes in various systems [e.g., conventional (Conv.) vs.
NASIS vs. PEDON Description Program codes (PDP)] and several
columns may be shown to facilitate conversions. The preferred,
standard code is shown bold. If only 1 untitled code column is shown,
it can be assumed that the conventional, NASIS, and PDP codes are all
the same.
Standard Terms vs. Creativity: Describe and record what you observe.
Choice lists in this document are a minimal set of descriptors. Use
additional descriptors, notes, and sketches to record pertinent
information and/or features for which no data element exists. Record
such information as free-hand notes under Miscellaneous Field Notes
(or User Defined Entries in PDP).
Changes: Soil Science is an evolving field. Changes to this Field Book
should and will occur. Please send comments or suggestions to the
authors at the National Soil Survey Center, USDA-NRCS;
100 Centennial Mall North, Rm. 152; Lincoln, NE 68508-3866.
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ACKNOWLEDGMENTS ................................................. i
FOREWORD .................................................................. ii
SITE DESCRIPTION ................................................... 1-1
Describer(s) Name.................................................................................. 1-1
Date ........................................................................................................ 1-1
Climate.................................................................................................... 1-1
Weather Conditions ............................................................................ 1-1
Air Temperature.................................................................................. 1-1
Soil Temperature ................................................................................ 1-1
[Soil Temperature, Soil Temperature Depth]
Location .................................................................................................. 1-2
[Latitude, Longitude, Datum Name]
Topographic Quadrangle ........................................................................ 1-2
Soil Survey Area Identification Number (SSID) ...................................... 1-2
County FIPS Code.................................................................................. 1-3
MLRA ...................................................................................................... 1-3
Transects ................................................................................................ 1-3
[Transect ID, Stop Number, Interval]
Series Name ........................................................................................... 1-4
Geomorphic Information ......................................................................... 1-4
Physiographic Location ...................................................................... 1-4
[Physiographic Division, Physiographic Province,
Physiographic Section, State Physiographic Area, Local
Physiographic/Geograpic Name]
Geomorphic Description ..................................................................... 1-4
[Landscape, Landform, Microfeature, Anthropogenic Feature]
Surface Morphometry ......................................................................... 1-4
[Elevation, Slope Aspect, Slope Gradient, Slope Complexity,
Slope Shape, Hillslope - Profile Position, Geomorphic
Component (Hills, Terraces, Mountains, Flat Plains),
Microrelief]
Water Status ........................................................................................... 1-9
Drainage ............................................................................................. 1-9
Flooding............................................................................................ 1-10
[Frequency, Duration, Months]
Ponding............................................................................................. 1-11
[Frequency, Depth, Duration]
(Soil) Water State ............................................................................. 1-12
Depth To Water Table ...................................................................... 1-13
(Seasonal) High Water Table - Kind ............................................ 1-13
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Vegetation / Land Cover ....................................................................... 1-14
[Earth Cover - Kind, Plant Symbol, Plant Common Name, Plant
Scientific Name]
Parent Material...................................................................................... 1-16
Bedrock................................................................................................. 1-18
[Kind, Fracture Interval Class, Hardness, Weathering Class, Depth]
Erosion.................................................................................................. 1-20
[Kind, Degree Class]
Runoff ................................................................................................... 1-21
Surface Runoff.................................................................................. 1-21
The Index (Of) Surface Runoff Class................................................ 1-22
Surface Fragments (Formerly Surface Stoniness)................................ 1-22
Diagnostic Horizons Or Properties........................................................ 1-23
[Kind, Depth]
References............................................................................................ 1-24
Profile / Pedon Description....................................... 2-1
Observation Method................................................................................ 2-1
[Kind, Relative Size]
Taxonomic Classification ........................................................................ 2-2
Horizon Nomenclature ............................................................................ 2-2
Master, Transitional And Common Horizon Combinations................. 2-2
Horizon Suffixes.................................................................................. 2-3
Other Horizon Modifiers...................................................................... 2-4
[Numerical Prefixes, Numerical Suffixes, The Prime]
Diagnostic Horizons............................................................................ 2-4
Horizon Depth..................................................................................... 2-4
Horizon Thickness .............................................................................. 2-5
Horizon Boundary ............................................................................... 2-5
[Distinctness, Topography]
Soil Color ................................................................................................ 2-7
Decision Flowchart For Describing Soil Colors .................................. 2-7
(Soil) Matrix Color............................................................................... 2-7
[(Soil) Color, Moisture State, Location Or Condition]
Mottles ................................................................................................ 2-9
[Quantity, Size, Contrast, Color, Moisture State, Shape]
Redoximorphic Features (RMF) Discussion ......................................... 2-13
Redoximorphic Features....................................................................... 2-14
[Kind, Quantity, Size, Contrast, Color, Moisture State, Shape,
Location, Hardness, Boundary]
Concentrations Discussion ................................................................... 2-17
Concentrations...................................................................................... 2-18
[Kind, Quantity (Percent Of Area Covered), Size, Contrast, Color,
Moisture State, Shape, Location, Hardness, Boundary]
Ped & Void Surface Features ............................................................... 2-24
[Kind, Amount, Continuity, Distinctness, Location, Color]
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(Soil) Texture ........................................................................................ 2-28
Texture Class.................................................................................... 2-28
Texture Triangle (Fine Earth)............................................................ 2-29
Texture Modifiers.............................................................................. 2-29
Texture Modifiers.............................................................................. 2-32
Compositional Texture Modifiers ...................................................... 2-33
Terms Used In Lieu Of Texture ........................................................ 2-34
Rock And Other Fragments .................................................................. 2-35
[Kind, Volume Percent, Roundness, Size Classes And Descriptive
Terms]
(Soil) Structure ...................................................................................... 2-38
[Type, Grade, Size]
Consistence .......................................................................................... 2-46
Rupture Resistance .......................................................................... 2-46
[Blocks, Peds, And Clods; Surface Crust And Plates]
Cementing Agents ............................................................................ 2-48
Manner Of Failure............................................................................. 2-49
Stickiness ......................................................................................... 2-50
Plasticity ........................................................................................... 2-50
Penetration Resistance..................................................................... 2-51
Excavation Difficulty ......................................................................... 2-52
Roots..................................................................................................... 2-53
[Quantity, Size, Quantity (diagram), Location]
Pores Discussion .................................................................................. 2-56
Pores..................................................................................................... 2-56
[Quantity, Size, Shape, Vertical Continuity]
Cracks................................................................................................... 2-58
[Kind, Depth, Relative Frequency]
Special Features................................................................................... 2-61
[Kind, Area (%) Occupied]
Permeability / Saturated Hydraulic Conductivity (Discussion) .............. 2-62
Permeability .......................................................................................... 2-63
Saturated Hydraulic Conductivity (Ksat)................................................. 2-63
Chemical Response.............................................................................. 2-64
Reaction (pH).................................................................................... 2-64
Effervescence................................................................................... 2-65
[Class, Location, Chemical Agent]
Reduced Conditions ......................................................................... 2-66
Salinity .............................................................................................. 2-66
Sodium Adsorption Ratio (SAR) ....................................................... 2-66
Odor ...................................................................................................... 2-67
Miscellaneous Field Notes.................................................................... 2-67
Minimum Data Set (For A Soil Description) .......................................... 2-67
Profile Description Form ....................................................................... 2-67
Profile Description Example.................................................................. 2-67
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Profile Description Report Example (For Soil Survey Reports) ............ 2-68
References............................................................................................ 2-68
Geomorphic Description........................................... 3-1
Geomorphic Description System (Version 2.06 - 9/4/97)........................ 3-1
Part I: Physiographic Location........................................................... 3-2
Part II: Geomorphic Description (Outline)........................................ 3-10
Part II: Geomorphic Description....................................................... 3-11
Part III: Surface Morphometry.......................................................... 3-22
References............................................................................................ 3-26
Soil Taxonomy ........................................................... 4-1
Introduction ............................................................................................. 4-1
Horizon Nomenclature ............................................................................ 4-1
Master And Transitional Horizons ...................................................... 4-1
Horizon Suffixes.................................................................................. 4-3
Horizon Nomenclature Conversion Charts ......................................... 4-5
Texture Triangle: Soil Texture Family Classes.................................. 4-7
Combined Texture Triangles: Soil Texture Family Classes
And Fine Earth Texture Classes .................................................... 4-8
References.............................................................................................. 4-9
Geology ...................................................................... 5-1
Introduction ............................................................................................. 5-1
Bedrock - Kind ........................................................................................ 5-1
Rock Charts ............................................................................................ 5-3
Igneous Rocks Table.......................................................................... 5-4
Metamorphic Rocks Table.................................................................. 5-5
Sedimentary And Volcaniclastic Rocks Table .................................... 5-6
North American Geologic Time Scale..................................................... 5-7
Till Terms ................................................................................................ 5-8
Volcaniclastic Terms............................................................................... 5-9
References............................................................................................ 5-10
Location...................................................................... 6-1
Public Land Survey................................................................................. 6-1
Townships And Ranges...................................................................... 6-1
Sections.............................................................................................. 6-2
Sub-Divisions...................................................................................... 6-3
State Plane Coordinate System.............................................................. 6-4
Universal Transverse Mercator (UTM) Rectangular
Coordinate System............................................................................. 6-4
References.............................................................................................. 6-5
Miscellaneous ............................................................ 7-1
Examples Of Percent Of Area Covered.................................................. 7-1
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Measurement Equivalents & Conversions.............................................. 7-2
Metric To English................................................................................ 7-2
English To Metric................................................................................ 7-3
Common Conversion Factors............................................................. 7-4
Guide To Map Scales And Minimum-Size Delineations ......................... 7-7
Common Soil Map Symbols (Traditional) ............................................... 7-8
Field Sampling ........................................................... 8-1
Introduction ............................................................................................. 8-1
Soil Sampling.......................................................................................... 8-1
Soil Sample Kinds .............................................................................. 8-1
Reference Samples........................................................................ 8-1
Characterization Samples.............................................................. 8-1
Sampling Strategies............................................................................ 8-1
Field Equipment Checklist .................................................................. 8-2
Examples Of Common Field Sampling Equipment ............................ 8-3
References.............................................................................................. 8-4
Index ....................................................................................................... 9-1
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Compiled by: P.J. Schoeneberger, D.A. Wysocki, E.C. Benham, NRCS,
Lincoln, NE; W. D. Broderson, NRCS, Salt Lake City, UT.
DESCRIBER(S) NAME
NAME (or initials) - Record the observer(s) who make the description;
e.g., Erling E. Gamble or EEG.
DATE
MONTH / DAY / YEAR - Record the date of the observations. Use two digits
for each; e.g., 05/21/96 (for May 21, 1996).
CLIMATE
Document the prevailing, general weather conditions at the time of
observation. (Not a data element in PDP; a site-condition which affects
some field methods; e.g., Ksat). Record the dominant Weather Conditions
and Air Temperature; e.g., Rain, 27C.
Weather Conditions
Sunny / Clear
Partly Cloudy
Overcast
Rain
Sleet
Snow
Code
SU
PC
OV
RA
SL
SN
AIR TEMPERATURE - The ambient air temperature at approximately chest
height (in degrees, Celsius or Fahrenheit); e.g., 27C.
SOIL TEMPERATURE - Record the ambient Soil Temperature and the
Depth at which it is determined; e.g., 22C, 50 cm. (NOTE: Soil Taxonomy
generally requires a depth of 50 cm.) Soil temperature should only be
determined from a freshly excavated surface that reflects the ambient soil
conditions. Avoid surfaces equilibrated with air temperatures.
Soil Temperature - Record the soil temperature (in C or F).
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Soil Temperature Depth - Record the depth at which the ambient soil
temperature is measured; e.g., 50 cm.
LOCATION
Record the geographical location of the point / area of interest as precisely
as possible. Latitude and Longitude are preferred. Record: degrees,
minutes, seconds (decimal seconds), direction, and associated Datum.
LATITUDE - e.g., 46 10' 19.38" N. Lat.
LONGITUDE - e.g., 95 23' 47.16" W. Long.
NOTE: Latitude and Longitude are required in NASIS. For other location
descriptors (e.g., Public Land Survey, UTM, Metes and Bounds, State Plane
Coordinates, etc.), see the “Location Section”.
DATUM NAME - Record the reference datum for the Latitude and Longitude
from either topographic maps or GPS configuration used; e.g., NAD 1983
(North American Datum, 1983) for most of the U.S.
TOPOGRAPHIC QUADRANGLE
Record the appropriate topographic map name (i.e., Quadrangle Name)
covering the observation site (commonly a USGS topographic map). Include
the scale (or map “series”) and the year printed; e.g., Pollard Creek - NW;
TX; 1:24,000; 1972.
SOIL SURVEY AREA IDENTIFICATION NUMBER
(SSID)
An identification number must be assigned if samples are collected for
analyses at the National Soil Survey Laboratory. This identifier consists of
four required and one optional part. These are:
1)
2)
3)
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The letter S (for “soil characterization sample”) and the two-digit
calendar year; e.g., S96 (for 1996).
The two-character state abbreviation; e.g., OK (for Oklahoma).
For non-USA samples, use the abbreviation FN.
The three-digit county FIPS code; e.g., 061 (for Haskell County,
OK). For non-USA samples, use the appropriate three-digit GSA
world-wide geographical location code (Public Building Service,
1996).
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4)
5)
A three-digit, sequential code to identify the individual pedons
sampled within the county or other survey area during any given
calendar year; e.g., 005. (NOTE: This sequential code starts
over with 001 each January 1.)
(Optional) A one-character sub-sample code. This is generally
used to indicate some relationship (such as satellite samples)
between sampling sites; e.g., A.
A complete example is S96OK061005A. [Translation: A pedon sampled for
soil characterization during 1996 (S96), from Oklahoma (OK), in Haskell
County (061), it’s the fifth pedon (005) sampled in that county during 1996,
and it’s a satellite sample (A) related to the primary pedon.]
COUNTY FIPS CODE
This is the three-digit FIPS code for the county (National Institute of
Standards and Technology, 1990) in a U.S. state in which the pedon or site
is located. It is usually an odd number; e.g., 061 (for Haskell County, OK).
For non-USA samples, enter FN followed by the appropriate three-digit GSA
world-wide geographical location code (Public Building Service, 1996); e.g.,
FN260 (for Canada).
MLRA
This is the one- to three-digit (and one-character sub-unit, if applicable) Major
Land Resource Area identifier (SCS, 1981); e.g., 58C (for Northern Rolling
High Plains - Northeastern Part).
TRANSECTS
If the soil description is a point along a transect, record the appropriate
transect information: Transect ID, Stop Number, and Interval. In NASIS,
additional transect information can be recorded: Transect Kind (random
point, fixed interval), Transect Selection Method (random, biased),
Delineation Size (units), Transect Direction (compass heading in degrees).
TRANSECT ID - This is a four- to five-digit number that identifies the
transect; e.g., 0029 (the 29th transect within the survey area).
STOP NUMBER - If the sample/pedon is part of a transect, enter the twodigit stop number along the transect; e.g., 07. (NOTE: NASIS allows up to
13 characters).
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INTERVAL - Record distances between observation points, compass
bearings, and GPS coordinates; or draw a route map in the Field Notes
(“User Defined Section”). In PDP, if the observation is part of a transect,
enter the distance (in feet or meters) between points; e.g., 30 m.
SERIES NAME
This is the assumed Soil Series name at the time of the description; e.g.,
Cecil. (If unknown, enter SND for “Series Not Designated”). (NOTE: The
field-assigned series name may ultimately change after additional data
collection and lab analyses.)
GEOMORPHIC INFORMATION
See the “Geomorphology Section” for complete choice lists. Codes are
shown following each example. Conventional “codes” traditionally consist of
the entire name; e.g., mountains.
PART 1: PHYSIOGRAPHIC LOCATION
Physiographic Division - e.g., Interior Plains or IN
Physiographic Province - e.g., Central Lowland or CL
Physiographic Section - e.g., Wisconsin Driftless Section or WDS
State Physiographic Area (Opt.) - e.g., Wisconsin Dells
Local Physiographic/Geographic Name (Opt.) - e.g., Bob’s Ridge
PART 2: GEOMORPHIC DESCRIPTION
Landscape - e.g., Foothills or FH
Landform - e.g., Ridge or RI
Microfeature - e.g., Mound or M
Anthropogenic Feature - e.g., Midden or H
PART 3: SURFACE MORPHOMETRY
Elevation - The height of a point on the earth’s surface, relative to
mean sea level (MSL). Use specific units; e.g., 106 m or 348 ft.
Recommended methods: Interpolation from topographic map contours;
altimeter reading tied to a known datum. NOTE: At present,
elevational determination by a sole Global Positioning System (GPS)
unit is considered unacceptably inaccurate.
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Slope Aspect - The compass direction (in degrees and accounting for
declination) that a slope faces, looking downslope; e.g., 287.
270
o
o
o
45
o
203
o
180
225
68
o
o
248
23
293
o
o
315
0
o
338
158
o
90
113
135
o
o
o
o
o
Slope Gradient - The angle of the ground surface (in percent) through
the site and in the direction that overland water would flow. Commonly
called “slope”. Make observations facing downslope to avoid errors
associated with some brands of clinometers; e.g., 18%.
Slope Complexity - Describe the relative uniformity (smooth linear or
curvilinear = simple or S) or irregularity (complex or C) of the ground
surface leading downslope through the point of interest; e.g., simple or
S.
Sim ple vs. Com plex
(S & W , 19 96 )
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Slope Shape - Slope shape is described in two directions: up-anddown slope (perpendicular to the contour), and across slope (along the
horizontal contour); e.g., Linear, Convex or LV.
LL
LV
LC
VL
VV
VC
CL
CV
CC
L = Linear
V = Convex
C = Concave
(S&W, 1996)
surface flow
pathway
Hillslope - Profile Position (Hillslope Position in PDP) - Twodimensional descriptors of parts of line segments (i.e., slope position)
along a transect that runs up and down the slope; e.g., backslope or
BS. This is best applied to transects or points, not areas.
Position
summit
shoulder
backslope
footslope
toeslope
Su
Code
SU
SH
BS
FS
TS
Sh
Sh
Bs
Fs
Ts
ch
an
ne
l
Bs
Su
Fs
Ts
Alluvium
(PJS, 1996; adapted from Ruhe, 1975)
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Geomorphic Component - Three-dimensional descriptors of parts of
landforms or microfeatures that are best applied to areas. Unique
descriptors are available for Hills, Terraces, Mountains, and Flat Plains;
e.g., (for Hills) nose slope or NS.
Hills
Code
NASIS
IF
HS
NS
SS
BS
PDP
S
sl ide
op
e
In
te
rf
Head
slope
lu
ve
IF
HS
NS
SS
---
interfluve
head slope
nose slope
side slope
base slope
se
Ba
e
op
Sl
Ba
se
low
Sl
er
op
ord
e
er
str
ea
m
m
viu
llu
co
Nose
slope
Alluvial
fill
higher
order
stream
(PJS, 1996; adapted from Ruhe, 1975)
Terraces
Code
RI
TR
riser
tread
Uplands
Terraces
riser
tread
Floodplain
Steps
Annual
Floodplain
100 yr Flood
(scarp)
(S&W, 1996)
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Mountains
mountaintop
mountainflank
upper third mountainflank
center third mountainflank
lower third mountainflank
mountainbase
Code
MT
MF
UT
CT
LT
MB
mountain top
- bare rock
- residuum
- short-trans.
colluvium
(crest, summit)
(mountain sideslopes)
mountain
flank
(colluvial apron)
- colluvium mantled slopes
- complex slopes
- long slopes
- rock outcrops (free faces)
- structural benches
(floodplain)
mountain
base
Colluvium
Alluvium
(S&W, 1996)
- thick colluvium
Flat Plains (proposed)
talf
rise
Code
-----
Microrelief - Small, relative differences in elevation between adjacent
areas on the earth’s surface; e.g., micro-high or MH; or micro-low or
ML.
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WATER STATUS
DRAINAGE - An estimate of the natural drainage class (i.e., the prevailing
wetness conditions) of a soil; e.g., somewhat poorly drained or SP.
Drainage Class
PDP
Very Poorly Drained
Poorly Drained
Somewhat Poorly Drained
Moderately Well Drained
Well Drained
Somewhat Excessively Drained
Excessively Drained
VP
P
SP
MW
W
SE
E
Code
NASIS
VP
PD
SP
MW
WD
SE
ED
The following definitions are the traditional, national criteria for Natural Soil
Drainage Classes (Soil Survey Staff, 1993). More specific, regional
definitions and criteria vary. (Contact an NRCS State Office for specific,
local criteria).
Very Poorly Drained - Water is at or near the soil surface during much
of the growing season. Internal free-water is shallow and persistent or
permanent. Unless the soil is artificially drained, most mesophytic
crops cannot be grown. Commonly, the soil occupies a depression or
is level. If rainfall is persistent or high, the soil can be sloping.
Poorly Drained - The soil is wet at shallow depths periodically during
the growing season or remains wet for long periods. Internal free-water
is shallow or very shallow and common or persistent. Unless the soil is
artificially drained, most mesophytic crops cannot be grown. The soil,
however, is not continuously wet directly below plow depth. The water
table is commonly the result of low or very low saturated hydraulic
conductivity class or persistent rainfall, or a combination of both factors.
Somewhat Poorly Drained - The soil is wet at a shallow depth for
significant periods during the growing season. Internal free-water is
commonly shallow to moderately deep and transitory to permanent.
Unless the soil is arificially drained, the growth of most mesophytic
plants is markedly restricted. The soil commonly has a low or very low
saturated hydraulic conductivity class, or a high water table, or receives
water from lateral flow, or persistent rainfall, or some combination of
these factors.
USDA - NRCS
1-9
5/13/98
Moderately Well Drained - Water moves through the soil slowly during
some periods of the year. Internal free water commonly is moderately
deep and may be transitory or permanent. The soil is wet for only a
short time within the rooting depth during the growing season. The soil
commonly has a moderately low, or lower, saturated hydraulic
conductivity class within 1 meter of the surface, or periodically receives
high rainfall, or both.
Well Drained - Water moves through the soil readily, but not rapidly.
Internal free-water commonly is deep or very deep; annual duration is
not specified. Water is available to plants in humid regions during
much of the growing season. Wetness does not inhibit growth of roots
for significant periods during most growing seasons. The soil is deep
to, or lacks redoximorphic features.
Somewhat Excessively Drained - Water moves through the soil
rapidly. Internal free water commonly is very rare or very deep. The
soils are commonly coarse-textured, have high saturated hydraulic
conductivity, and lack redoximorphic features.
Excessively Drained - Water moves through the soil very rapidly.
Internal free water commonly is very rare or very deep. The soils are
commonly coarse-textured, have very high saturated hydraulic
conductivity, and lack redoximorphic features.
FLOODING - Estimate the Frequency, Duration, and the Months flooding
is expected; e.g., rare, brief, Jan. - March.
Frequency Frequency
Class
PDP
NASIS
NO 2
NO
Very Rare
---
VR
Rare
Occasional 3
Frequent 3, 4
Very Frequent 4
RA
OC
FR
---
RA
OC
FR
VF
None
1
2
5/13/98
Code
Criteria: estimated,
average number of flood
events per time span 1
No reasonable chance
(e.g., < 1 time in 500 years)
1 time in 500 years, but
< 1 time in 100 years
1 to 5 times in 100 years
> 5 to 50 times in 100 years
> 50 times in 100 years
> 50% of all months in year 2
Flooding Frequency is an estimate of the natural, unmanaged
conditions (ignore influence by dams, levees, etc.).
In PDP, None class (< 1 time in 100 years) spans both None and
Very Rare NASIS classes.
1-10
USDA - NRCS
3
4
Historically, Occasional and Frequent classes could be combined
and called Common; not recommended.
Very Frequent class takes precedence over Frequent, if applicable.
Duration Duration
Class
Extremely Brief
Very Brief
Brief
Long
Very Long
Code
Criteria:
estimated, average
duration per flood event
0.1 to < 4 hours
4 to < 48 hours
2 to < 7 days
7 to 30 days
30 days
EB
VB
BR
LO
VL
Months - Estimate the begining and ending month(s) of the year that
flooding generally occurs; e.g., Dec. - Feb.
PONDING - Estimate or monitor the Frequency, Depth, and Duration of
standing water. In PDP, also note the months ponding generally occurs. A
complete example is: occasional, 50 cm, brief, Feb - Apr.
Frequency Frequency
Class
None
Rare
Occasional
Frequent
Code
NO
RA
OC
FR
Criteria: estimated
average # of ponding events
per time span
< 1 time in 100 years
1 to 5 times in 100 years
> 5 to 50 times in 100 years
> 50 times in 100 years
Depth - Estimate the average, representative depth of ponded water at
the observation site and specify units; e.g., 1 ft, or 30 cm.
Duration Duration
Class
Very Brief
Brief
Long
Very Long
USDA - NRCS
Code
VB
BR
LO
VL
1-11
Criteria:
estimated average time per
ponding event
< 2 days
2 to < 7 days
7 to < 30 days
30 days
5/13/98
(SOIL) WATER STATE - (In NASIS and PDP this data element is called Soil
Moisture Status.) Estimate the water state of the soil at the time of
observation; e.g., wet, satiated. Soil temperature must be above 0C. To
record conditions with temperatures < 0C (frozen water); for permanently
frozen conditions, see Texture Modifiers or Terms Used in Lieu of
Texture in the “Profile Description Section”. NOTE: Criteria have changed.
Water State
Class
Dry 1
Moist 1
Code
D
M
Wet
W
Wet,
Non-satiated 4
WN
Wet,
Satiated 4
WS
1
2
3
4
Criteria:
tension
> 1500 kPa
1500 to > 1
or > 0.5 kPa 2
< 1.0 or
< 0.5 kPa 2
> 0.01 and
< 1.0 kPa or
< 0.5 kPa 2
No Free Water
< 0.01 kPa,
Free Water
Traditional Criteria:
tension and field
> 15 bars of tension 3
Former Usage: > 1/3 to
15 bars of tension (field
capacity to wilting point)
0 - 1/3 bars tension
(field capacity or wetter)
Water films are visible;
sand grains and peds
glisten, but no free water
is present
Free water easily visible
Additional subclasses of water state can be recognized for Dry and
Moist classes, if desired (Soil Survey Staff, 1993; p. 91).
Use the 1 kPa limit for all textures, except those coarser than loamy
fine sand (Soil Survey Staff, 1993; p. 90).
Convention assumes 15 bars of tension as the wilting point for most
annual, agricultural row-crops. Caution: Various perennials, shrubs,
trees, and other native vegetation have wilting points up to 66 bars
tension (= 6600 kPa) or more.
Satiation vs. Saturation: Satiation implies minor amounts of
entrapped air in the smallest pores. True saturation excludes
entrapped air. Satiation, for practical purposes, is saturation.
Temporal monitoring of a water table by piezometer or other accepted
methods may be needed to verify saturation. Related terms used for
classifying soils (i.e., Soil Taxonomy) follow. Endosaturation is
saturation in all layers to > 200 cm (80 inches). Episaturation requires
saturated layers that overlie unsaturated layers within the upper 2 m
(80 inches). Anthric saturation, a variant of episaturation, is saturation
due to management-induced flooding (e.g., for rice or cranberry
production).
5/13/98
1-12
USDA - NRCS
DEPTH TO WATER TABLE - Measure or estimate the depth from the
ground surface to the stabilized contact with free-standing water in an open
bore-hole or well. Historically, record Seasonal High Water Table - Kind,
and Frequency (duration, beginning month, and days); specify units (e.g.,
cm, ft). If seasonally variable water is absent at time of observation, it is
common practice to estimate prevailing water table conditions based upon
soil morphology (e.g., presence of Redoximorphic Features of chroma 2) in
lieu of water-table monitoring data.
NOTE: Within NRCS’s PDP and NASIS databases the traditional
designation of Seasonal High Water Table - Kind and Frequency are
replaced. In PDP (PEDON), all water table information is recorded in a
temporal table. Record Depth to Stabilized Free Water and Date of
Observation. In NASIS, all water table information is replaced by
(Soil) Water State for each layer at the time of description; e.g., layer A
is moist, layer B is wet, layer C is dry. For map unit component
descriptions, (Soil) Water State is recorded (by layer) on a monthly
basis, in NASIS.
(Seasonal) High Water Table - Kind - Traditional types of intermittent
(e.g., seasonal) high water tables (Soil Survey Staff, 1983). Obsolete
in NASIS.
Kind
Code
Criteria:
PDP
1
Apparent
A
Artesian
---
Perched
P
Ponding 1
---
Level of stabilized water in a fresh,
unlined borehole.
The final water level within a cased
borehole in which the water level rises
above an impermeable layer due to a
positive hydrostatic head.
A water table that lies above an
unsaturated zone. The water table
will fall if the borehole is extended.
Standing water in a closed depression
on top of the soil.
A kind of intermittent water table, but not a seasonal high water
table (Soil Survey Staff, 1983).
USDA - NRCS
1-13
5/13/98
VEGETATION / LAND COVER
EARTH COVER - KIND - Record the dominant land cover at the site; e.g.,
intermixed hardwoods & conifers. (Similar to Landuse in PDP.)
Kind 1
Code
Kind 1
Code
ARTIFICIAL COVER (A) - Nonvegetative cover; due to human activity.
rural transportation - roads,
ARU urban and built-up - cities,
AUR
railroads
farmsteads, industry
BARREN LAND (B) - < 5% vegetative cover naturally or from construction.
culturally induced - saline seeps,
BCI other barren - salt flats, mud
BOB
mines, quarries, and oil-waste
flats, slickspots, badlands
areas
permanent snow or ice
BPS rock
BRK
sand or gravel
BSG
CROP COVER (C) - includes entire cropping cycle (land prep, crop, or crop
residue) for annual or perennial herbaceous plants.
close-grown crop - wheat, rice,
CCG row crop - corn, cotton,
CRC
oats, and rye; small grains
soybeans, tomatoes, and other
truck crops, tulips
GRASS / HERBACEOUS (G) - > 50% grass, grass-like (sedge/rushes), or forb
cover, mosses, lichens, ferns; non-woody.
hayland - alfalfa, fescue,
GHL rangeland, savanna GRS
bromegrass, timothy
10 to 20% tree cover
marshland - grasses and grassGML rangeland, shrubby GRH
like plants
20 to 50% shrub cover
pastureland, tame - fescues,
GPL rangeland, tundra
GRT
bromegrass, timothy, and
lespedeza
rangeland, grassland; < 10%
GRG other grass & herbaceous cover GOH
trees, < 20%shrubs; rangeland
used for hayland
SHRUB COVER (S) - > 50% shrub or vine canopy cover.
crop shrubs - filberts, blueberry,
SCS native shrubs - shrub live oak,
SNS
ornamental nursery stock
mesquite, sage-brush, creosote
bush; rangeland > 50% shrub
cover
crop vines - grapes, blackberries, SCV other shrub cover
SOS
raspberries
5/13/98
1-14
USDA - NRCS
TREE COVER (T) - > 25% canopy cover by woody plants, natural or planted.
conifers - spruce, pine, fir
TCD swamp - trees, shrubs
TSW
crop, trees - nuts, fruit, nursery,
TCR tropical - mangrove and royal
TTR
Christmas trees
palms
hardwoods - oak, hickory, elm,
THW other tree cover
TOC
aspen
intermixed hardwoods & conifers - TIM
oak-pine mix
WATER (W) - water at the soil surface; includes seasonaly frozen water.
1
Land Cover Kinds are presented at two levels of detail: Bolded table
subheadings are the “NASIS - Level 1” choices (NSSH, Part 622, p. 8; Soil
Survey Staff, 1996c). Individual choices under the subheadings are the
“NASIS - Level 2” choices.
PLANT SYMBOL - Record the codes (scientific plant name abbreviations)
for the major plant species found at the site (NRCS, 1996); e.g., ANGE
(Andropogon gerardii or big bluestem). NOTE: This is the primary plant data
element in NASIS.
PLANT COMMON NAME - Record the common names of the major plant
species found at the site [NRCS, 1996 (electronic file); SCS, 1989 (hard
copy)]; e.g., cottonwood, big bluestem. This item may be recorded as a
secondary data element to augment the Plant Symbol. CAUTION: Multiple
common names exist for some plants; not all common names for a given
plant are in the National Plants database.
PLANT SCIENTIFIC NAME - Record the scientific plant name along with or
in lieu of common names; e.g., Acer rubrum (Red Maple). [NOTE: Although
used in the past, scientific names of plants (SCS, 1989) are not presently
recorded by the NRCS; e.g., PDP has no data element for and does not
recognize scientific plant names.] (NOTE: NASIS codes for common plant
names are derived from the scientific names.)
USDA - NRCS
1-15
5/13/98
PARENT MATERIAL
Record the Kind(s) of unconsolidated material (regolith) from which the soil
is derived. If the soil is derived directly from the underlying bedrock (e.g.,
granite), identify the Parent Material as either grus, saprolite, or residuum
and then record the appropriate Bedrock - Kind choice. Multiple parent
materials, if present, should be denoted; e.g., loess, over colluvium, over
residuum. Use numerical prefixs in the Horizon designations to denote
different parent materials (lithologic discontiniuities); e.g., A, BE, 2Bt, 2BC,
3C.
KIND - e.g., saprolite, loess, colluvium.
Kind 1
Code
Kind 1
Code
PDP NASIS
NASIS
EOLIAN DEPOSITS (non-volcanic)
eolian deposit
E
EOD loess, calcareous
-CLO
eolian sands
S
EOS loess, noncalcareous
-NLO
loess
W
LOE
parna
-PAR
GLACIAL DEPOSITS
drift
D
GDR till, ablation
-ATI
glaciofluvial deposit
-GFD till, basal
-BTI
glaciolacustrine deposit
-GLD till, flow
-FTI
glaciomarine deposit
-GMD till, lodgement
-LTI
outwash
G
OTW till, melt-out
-MTI
supraglacial debris-flow
-SGF till, supraglacial
-UTI
till
T
TIL
till, supraglacial melt-out -PTI
IN-PLACE DEPOSITS (non-transported)
grus 2
-GRU saprolite 2
-SAP
residuum 2
X
RES
MASS MOVEMENT DEPOSITS 4
mass movement deposit -MMD mudflow deposit
-MFD
block glide deposit
-BGD rockfall avalanche dep.
-RAD
colluvium
V
COL rockfall deposit
-RFD
creep deposit
-CRP rotational landslide dep.
-RLD
debris avalanche deposit -DAD scree
-SCR
debris flow deposit
-DFD soil fall deposit
-SFD
debris slide deposit
-DSD talus
-TAL
earthflow deposit
-EFD
topple deposit
-TOD
lateral spread deposit
-LSD
PDP
5/13/98
1-16
USDA - NRCS
MISCELLANEOUS DEPOSITS
cryoturbate
-CRY mine spoil or earthy fill
F
diamicton
-DIM
ORGANIC DEPOSITS 5
coprogenic materials
-COM organic, grassy materials -diatomaceous earth
-DIE
organic, herbaceous mat. -marl
-MAR organic, mossy materials -organic materials
O
ORM organic, woody materials -VOLCANIC DEPOSITS (unconsolidated; eolian and mass movement)
ash (< 2 mm)
H
ASH cinders (2-64 mm)
-ash, acidic
-ASA
lahar (volcaniclastic flow) -ash, andesitic
-ASN lapilli
-(2-64 mm, > 2.0 sg 3)
ash, basaltic
-ASB
pumice (< 1.0 sg 3)
-ash, basic
-ASC scoria (> 2.0 sg 3)
-ash flow (pyroclastic)
-ASF
tephra (all ejecta)
-bombs (> 64 mm)
-BOM
WATER LAID or TRANSPORTED DEPOSITS
alluvium
A
ALL
marine deposit
M
backswamp deposit
-BSD overbank deposit
-beach sand
-BES
pedisediment
-estuarine deposit
Z
ESD slope alluvium
-lacustrine deposit
L
LAD
valley side alluvium
-1
2
3
4
5
MSE
OGM
OHM
OMM
OWM
CIN
LAH
LAP
PUM
SCO
TEP
MAD
OBD
PED
SAL
VSA
Parent material defintions are found in the “Glossary of Landforms and
Geologic Terms”, NSSH - Part 629 (Soil Survey Staff, 1996c), or the
“Glossary of Geology” (Bates et al., 1987).
Use the most precise term for the in situ material. Residuum is the most
generic term.
sg = specific gravity = the ratio of a material’s density to that of water
[weight in air / (weight in air - weight in water)].
Cruden and Varnes, 1996.
These generic terms refer to the dominant, origin of the organic materials
or deposits from which the organic soil has formed (i.e. parent material)
(Soil Survey Staff, 1993). These terms partially overlap with those
recognized in Soil Taxonomy (terms which refer primarily to what the
organic material presently is); see the “Diagnostic Horizons Table” or
“Properties Table”.
USDA - NRCS
1-17
5/13/98
BEDROCK
Describe the nature of the continuous hard rock underlying the soil. Specify
the Kind, Fracture Interval, Hardness, and Weathering Class.
KIND - e.g., limestone.
Kind
Code 1
NASIS
IGNEOUS-INTRUSIVE
diabase
-diorite
-gabbro
-granite
I4
granodiorite
-IGNEOUS-EXTRUSIVE
aa (lava)
P8
andesite
I7
basalt
I6
dacite
-latite
-obsidian
-IGNEOUS-PYROCLASTIC
ignimbrite
-pyroclastics (coherent) P0
tuff
P1
tuff, acidic
P2
tuff, basic
P3
METAMORPHIC
amphibolite
-gneiss
M1
granofels
-granulite
-greenstone
-hornfels
-marble
L2
metaconglomerate
-metaquartzite
M9
5/13/98
Code 1
NASIS
Kind
PDP
PDP
DIA
DIO
GAB
GRA
GRD
monzonite
peridotite
pyroxenite
syenite
syenodiorite
------
MON
PER
PYX
SYE
SYD
AAL
AND
BAS
DAC
LAT
OBS
pahoehoe (lava)
pumice (flow, coherent)
rhyolite
scoria (coherent, mass)
trachyte
P9
E6
-E7
--
PAH
PUM
RHY
SCO
TRA
IGN
PYR
TUF
ATU
BTU
tuff breccia
volcanic breccia
volcanic breccia, acidic
volcanic breccia, basic
P7
P4
P5
P6
TBR
VBR
AVB
BVB
AMP
GNE
GRF
GRL
GRE
HOR
MAR
MCN
MQT
metavolcanics
migmatite
mylonite
phyllite
schist
serpentinite
slate
soapstone (talc)
----M5
M4
M8
--
MVO
MIG
MYL
PHY
SCH
SER
SLA
SPS
1-18
USDA - NRCS
SEDIMENTARY-CLASTICS
arenite
-ARE
porcellanite
argillite
-ARG
sandstone
arkose
A2
ARK
sandstone, calcareous
breccia, non-volcanic
-NBR
shale
(angular fragments)
claystone
-CST
shale, acid
conglomerate
C0
CON
shale, calcareous
(rounded fragments)
conglomerate, calcar.
C2
CCN
shale, clayey
graywacke
-GRY
siltstone
mudstone
-MUD
siltstone, calcareous
orthoquartzite
-OQT
EVAPORITES, ORGANICS, AND PRECIPITATES
chalk
L1
CHA
limestone, arenaceous
chert
-CHE
limestone, argillaceous
coal
-COA
limestone, cherty
dolomite
L3
DOL
limestone, phosphatic
gypsum
-GYP
travertine
limestone
L0
LST
tufa
INTERBEDDED
limestone-sandst.-shale B1
LSS
sandstone-shale
limestone-sandstone
B2
LSA
sandstone-siltstone
limestone-shale
B3
LSH
shale-siltstone
limestone-siltstone
B4
LSI
1
-A0
A4
H0
POR
SST
CSS
SHA
-H2
ASH
CSH
H3
T0
T2
YSH
SIS
CSI
L5
L6
L7
L4
---
ALS
RLS
CLS
PLS
TRV
TUA
B5
B6
B7
SSH
SSI
SHS
Definitions for bedrock are found in the “Glossary of Landforms and
Geologic Terms”, NSSH - Part 629 (Soil Survey Staff, 1996c), and in the
“Glossary of Geology” (Bates, et al., 1987).
FRACTURE INTERVAL CLASS Average Distance
Between Fractures
< 10 cm
10 to < 45 cm
45 to < 100 cm
100 to < 200 cm
200 cm
USDA - NRCS
Code
1
2
3
4
5
1-19
5/13/98
HARDNESS (Obsolete -- used in PDP. NASIS uses Dry Rupture
Resistance classes (excluding Loose) and criteria.) Hardness Class
Hard
Soft
1
Code
H
S
Criteria:
Excavation Difficulty is VH or EH 1
Paralithic contact criteria 2
Very Hard (VH) and Extremely Hard (EH) classes from the
“Consistence-Excavation Difficulty Table”.
See Keys to Soil Taxonomy (Soil Survey Staff, 1996b).
2
WEATHERING CLASS - The relative extent to which a bedrock has
weathered as compared to a presumed, non-weathered state.
Class
Slight
Moderate
Strong
Code
SL
MO
ST
Criteria
Not Available
DEPTH (TO BEDROCK) - Record the depth (cm) from the ground surface to
the contact with coherent (continuous) bedrock.
EROSION
Estimate the dominant kind and magnitude of accelerated erosion at the site.
Specify the Kind and Degree.
KIND Kind
PDP
Wind
Water
Sheet
Rill
Gully
Tunnel
1
2
3
I
W
---------
Code
NASIS
I
--S
R
G
T
Criteria 1
Deflation by wind
Removal by running water
Even soil loss, no channels
Small channels 2
Big channels 3
Subsurface voids within soil that
enlarge by running water (i.e.
piping)
Soil Survey Staff, 1993, p82.
Small, runoff channels that can be obliterated by conventional tillage.
Large, runoff channels that cannot be obliterated by conventional
tillage.
5/13/98
1-20
USDA - NRCS
DEGREE CLASS Class
None
1
2
3
4
1
Code
0
1
2
3
4
Criteria: Estimated % loss of the original
A & E horizons or, the estimated loss of
the upper 20 cm (if original combined
A & E horizons were < 20 cm thick). 1
0%
> 0 up to 25%
25 up to 75%
75 up to 100%
> 75% & total removal of A
Soil Survey Staff; 1993, pp 86-89.
RUNOFF
SURFACE RUNOFF - Surface runoff (Hortonian flow, overland flow) is the
flow of water from an area that occurs over the surface of the soil. Surface
runoff differs from internal flow, or throughflow, that results when infiltrated
water moves laterally or vertically within a soil, above the watertable. “The
Index (of) Surface Runoff Classes” are relative estimates of surface runoff
based on slope gradient and saturated hydraulic conductivity (Ksat). This
index is specific to the following conditions (Soil Survey Staff, 1993).
The soil surface is assumed to be bare.
The soil is free of ice.
Retention of water by ground-surface irregularities is negligible or low.
Infiltration is assumed to be at at the steady ponded infiltration stage.
Water is added to the soil by precipitation or snowmelt that yields 50 mm
in 24-hours with no more than 25 mm in any 1-hour period.
Antecedent soil water state is assumed to be very moist or wet to: a) the
base of the solum; b) a depth of 1/2 m; or c) through the horizon that has
the minimum Ksat within the top 1 meter; whichever is the least depth.
Use the following table and the above conditions to estimate “The Index (of)
Surface Runoff Class” for the site. If seasonal or permanent, internal freewater occurs a depth of 50 cm (very shallow and shallow Internal Freewater classes), use a Ksat of Very Low. If seasonal or permanent, internal
free-water is deeper than 50 cm, use the appropriate Ksat from the table. In
PDP, if estimating runoff from vegetated areas, define and record under User
Defined Property.
USDA - NRCS
1-21
5/13/98
Slope
Gradient
Percent
Concave
<1
1 to < 5
5 to < 10
10 to < 20
20
1
Index (of) Surface Runoff Classes
Saturated Hydraulic Conductivity(Ksat) Class 1
Very High High Mod. High Mod. Low
Low
Very Low
- - - - - - - - - - - - - - - - - - - - - cm / hour - - - - - - - - - - - - - - - - - - - 36
3.6
0.36
0.036
0.0036 < 0.0036
to
to
to
to
< 36
< 3.6
< 0.36
< 0.036
N
N
N
N
N
N
N
N
N
L
M
H
N
VL
L
M
H
VH
VL
L
M
H
VH
VH
VL
L
M
H
VH
VH
L
M
H
VH
VH
VH
This table is based on the minimum Ksat occurring within 1/2 m of the
soil surface. If the minimum Ksat for the soil occurs between 1/2 to 1 m,
the runoff estimate should be reduced by one class (e.g., medium to
low). If the minimum Ksat for the soil occurs below 1 meter, use the
lowest Ksat class that occurs within 1 m of the surface.
Index (of) Surface Runoff
Class Names
Negligible
Very Low
Low
Medium
High
Very High
Code
N
VL
L
M
H
VH
SURFACE FRAGMENTS (formerly Surface Stoniness)
Record the amount of surface fragment1 cover (either as a class or as a
numerical percent), as determined by either a “point count” or “line-intercept”
method. In NASIS, additional details can be recorded: Surface Fragment
Kind, (use “Rock Fragment - Kind Table”), Mean Distance Between
Fragments (edge to edge), Shape [FL-flat or NF-nonflat], Size, Roundness
(use classes and criteria found in “Rock Fragment - Roundness Table”), and
Rock Fragment - Rupture Resistance.
5/13/98
1-22
USDA - NRCS
Surface Fragment Class 1
Code
Conv 2 NASIS
Stony or Bouldery
Very Stony or Very Bouldery
Extremely Stony or Ext. Bouldery
Rubbly
Very Rubbly
1
2
1
2
3
4
5
%
%
%
%
%
Criteria:
Percentage of
surface
covered
0.01 to < 0.1
0.1 to < 3
3 to < 15
15 to < 50
50
This data element is also used to record large wood fragments (e.g.,
tree trunks) on organic soils, if the fragments are a management
concern and appear to be relatively permanent.
Historically called Surface Stoniness classes (now Surface Fragment
classes). Use as a map-unit phase modifier is restricted to stone-sized
fragments, or larger (> 250 mm; Soil Survey Staff, 1953).
DIAGNOSTIC HORIZONS or PROPERTIES
Identify the Kind and Upper and Lower Depths of occurrence of Soil
Taxonomic diagnostic horizons and properties; e.g., mollic epipedon; 0 45 cm. Multiple features per horizon can be recorded. (Called Feature-Kind
in PDP.) In NASIS, Thickness (Representative Value (RV), High, Low) can
also be recorded.
KIND - (See definitions in current Keys to Soil Taxonomy.)
Kind
Code
Kind
NASIS
EPIPEDONS (Diagnostic Surface Horizons)
Anthropic
A
AN
Mollic
Folistic
-FO
Ochric
Histic
H
HI
Plaggen
Melanic
ME
ME
Umbric
DIAGNOSTIC SUBSURFACE HORIZONS
Agric
R
AG
Natric
Albic
Q
AL
Ortstein
Argillic
T
AR
Oxic
Calcic
C
CA
Petrocalcic
Cambic
B
CM
Petrogypsic
Duripan
Z
DU
Placic
Fragipan
F
FR
Salic
Glossic
TO
GL
Sombric
PDP
USDA - NRCS
1-23
PDP
Code
NASIS
M
O
P
U
MO
OC
PL
UM
N
-X
E
J
K
Y
I
NA
OR
OX
PE
PG
PA
SA
SO
5/13/98
Gypsic
G
GY
Spodic
Kandic
KA
KA
Sulfuric
DIAGNOSTIC PROPERTIES - MINERAL SOILS
Abrupt textural change
AC
AC
Lamella / Lamellae
Albic material
-AM
Lithic contact
IF
Albic material, interfinger
AI
Paralithic contact
Andic soil properties
AN
AP
Paralithic material
Aquic conditions
--AQ
Permafrost
Carbonates, secondary 1
LI
SC
Petroferric contact
Densic contact
-DC
Plinthite
Densic material
-DM
Slickensides
Durinodes
D
DN
Sulfidic material
Fragic soil properties
-FP
DIAGNOSTIC PROPERTIES - ORGANIC SOILS
Fibric soil materials
FI
FM
Limnic materials
Coprogenous earth
Hemic soil materials
HE
HM
Diatomaceous
Humilluvic materials
HU
UM
Sapric soil materials
1
SA
RM
earth
Marl
S
V
SP
SU
-L
W
-PF
PC
PL
SL
SU
LA
LC
PC
PM
PA
TC
PI
SS
SM
LM
CO
DI
LM
CO
DI
MA
MA
Secondary carbonates, replaces “soft, powdery lime”. NOTE: Gilgai (G
in PDP) is no longer a diagnostic feature in Soil Taxonomy.
DEPTH - Document the zone of occurrence for a diagnostic horizon or
property, as observed, by recording the upper and lower depth and specify
units; e.g., 22 - 39 cm. Record Top Depth and Bottom Depth.
REFERENCES
[References for this “Site Description Section” are combined with those at the
end of the “Profile / Pedon Description Section” on page 2-68.]
5/13/98
1-24
USDA - NRCS
Compiled by: D.A. Wysocki, P.J. Schoeneberger, E.C. Benham, NRCS,
Lincoln, NE; W. D. Broderson, NRCS, Salt Lake City, UT.
OBSERVATION METHOD
For each layer, indicate the type and relative extent of the exposure upon
which the primary observations are made. (Examples of common sampling
devices are included in the “Field Sampling Section”.) Describe Kind and
Relative Size.
KIND Kind
Code
“Disturbed” Samples
bucket auger
BA
screw auger
SA
Criteria: Types
(common size or ranges)
e.g., open, closed, sand, mud buckets
(5-12 cm diam.)
e.g., external thread hand augers,
power (flight) auger (2-30 cm diam.)
“Undisturbed” Samples
push tube
PT
e.g., hand held, hydraulic, hollow
stem (2-10 cm diam.)
shovel “slice” 1
SS
e.g., undisturbed block extracted with
a shovel (sharpshooter: 20 x 40 cm)
WALL / FLOOR - “Undisturbed” Area or Exposure
small pit
SP
e.g., hand dug (< 1 m x 2 m)
trench
TR
e.g., backhoe, pipeline (> 1 m x 2 m)
beveled cut
BC
e.g., roadcuts graded to < 60% slope
cut
CU
e.g., roadcut, streambank, mediumsized borrow pit wall > 60% slope
(e.g., > 4 m, < 33 m)
large open pit or
LP
large borrow pits, large or irregular
quarry
banks (e.g., > 33 m)
1
Field method used for hydric soil investigations.
RELATIVE SIZE - Record the approximate size of the exposure observed.
Use cm for “Drill Cores” and m for “Wall/Floor” observations; e.g., bucket
auger, 3 cm; trench wall, 3 m. (NOTE: Common size range for each method
is indicated in the “Criteria” column of the “Observation Method - Kind Table”.
These dimensions are not intended to be restrictive or precise; merely
approximate.)
USDA - NRCS
2-1
5/13/98
TAXONOMIC CLASSIFICATION
After completely describing the soil, classify the pedon as completely as
possible (to the lowest taxonomic level). See the most current version of
Keys to Soil Taxonomy or NASIS for a complete choice list; e.g., fine, mixed,
active, mesic Typic Haplohumult.
HORIZON NOMENCLATURE
Use capital letters to identify master horizons; e.g., A, B. Use suffixes
(lowercase letters) to denote additional horizon characteristics or features;
e.g., Ap, Btk. [For more detailed criteria, see the “Soil Taxonomy Section”;
for complete definitions see Keys to Soil Taxonomy (Soil Survey Staff,
1996).] Label a horizon only after all morphology is recorded.
MASTER, TRANSITIONAL AND COMMON HORIZON COMBINATIONS 1 Horizon
O
A
AB (or AE)
A/B (or A/E
or A/C)
AC
E
EA (or EB)
E/A
E and Bt
BA (or BE)
B/A (or B/E)
B
BC
5/13/98
Criteria
Predominantly organic matter (litter & humus)
Mineral, organic matter (humus) accumulation, loss of
Fe, Al, clay
Dominantly A horizon characteristics but also contains
some characteristics of the B (or E) horizon
Discrete, intermingled bodies of A and B (or E or C)
material; majority of horizon is A material
Dominantly A horizon characteristics but also contains
some characteristics of C horizon
Mineral, loss of Si, Fe, Al, clay, or organic matter
Dominantly E horizon characteristics but also contains
some attributes of the A (or B) horizon
Discrete, intermingled bodies of E and A horizon
material; majority of horizon is E material
Thin lamellae (Bt) within a dominantly E horizon
Dominantly B characteristics but also contains some
attributes of A (or E) horizon
Discrete, intermingled bodies of B and A (E) material;
majority of horizon is B material
Subsurface accumulation of clay, Fe, Al, Si, humus,
CaCO3, CaSO4; or loss of CaCO3; or accumulation of
sesquioxides; or subsurface soil structure
Dominantly B horizon characteristics but also contains
some characteristics of the C horizon
2-2
USDA - NRCS
B/C
CB (or CA)
C/B (or C/A)
C
R
W
1
2
Discrete, intermingled bodies of B and C material;
majority of horizon is B material
Dominantly C horizon characteristics but also contains
some characteristics of the B (or A) horizon
Discrete, intermingled bodies of C and B (or A)
material; majority of horizon is C material
Little or no pedogenic alteration, unconsolidated
earthy material, soft bedrock
Hard, continuous bedrock
A layer of liquid water (W) or permanently frozen water
(Wf) within the soil (excludes water/ice above soil) 2
Refer to the “Soil Taxonomy Section” for older horizon nomenclature.
NRCS Soil Classification Staff, 1997; personal communication.
HORIZON SUFFIXES - Historically referred to as “Horizon Subscripts”, and
more recently as “Subordinate Distinctions” 1. (Historical codes and
conversions are shown in the “Soil Taxonomy Section”.)
Horizon
Suffix 2
a
b
c
d
e
f
ff
g
h
i
j
jj
k
m
n
o
USDA - NRCS
Criteria
Highly decomposed organic matter
Buried genetic horizon (not used with C horizons)
Concretions or nodules
Densic layer (physically root restrictive)
Moderately decomposed organic matter
Permanently frozen soil or ice (permafrost); continuous,
subsurface ice; not seasonal
Permanently frozen soil (“Dry” permafrost); no continuous
ice; not seasonal 3
Strong gley
Illuvial organic matter accumulation
Slightly decomposed organic matter
Jarosite accumulation 3
Evidence of cryoturbation 3
Pedogenic carbonate accumulation
Strong cementation (pedogenic, massive)
Pedogenic, exchangeable sodium accumulation
Residual sesquioxide accumulation (pedogenic)
2-3
5/13/98
p
q
r
s
ss
t
v
w
x
y
z
1
2
3
Plow layer or other artificial disturbance
Secondary (pedogenic) silica accumulation
Weathered or soft bedrock
Illuvial sesquioxide accumulation
Slickensides
Illuvial accumulation of silicate clay
Plinthite
Weak color or structure within B (used only with B)
Fragipan characteristics
Pedogenic accumulation of gypsum
Pedogenic accumulation of salt more soluble than gypsum
Keys to Soil Taxonomy, 6th Edition, 1994.
Keys to Soil Taxonomy, 7th Edition, 1996.
NRCS Soil Classification Staff, 1997; personal communication.
OTHER HORIZON MODIFIERS Numerical Prefixes (2, 3, etc.) - Used to denote lithologic
discontinuities. By convention, 1 is understood but is not shown; e.g.,
A, E, Bt1, 2Bt2, 2BC, 3C1, 3C2.
Numerical Suffixes - Used to denote subdivisions within a master
horizon; e.g., A1, A2, E, Bt1, Bt2, Bt3, Bs1, Bs2.
The Prime ( ' ) -Used to indicate the second occurrence of an identical
horizon descriptor(s) in a profile or pedon; e.g., A, E, Bt, E' Btx, C. The
prime does not indicate either buried horizons (which are denoted by a
lower case “b”; e.g., Btb), or lithologic discontinuities (denoted by
numerical prefixes). Double and triple primes are used to denote
subsequent occurrences of horizon descriptors in a pedon; e.g., A, E,
Bt, E', Btx, E", Cd.
DIAGNOSTIC HORIZONS - See the “Diagnostic Horizons Table” or
“Properties Table”, in the “Site Description Section”.
HORIZON DEPTH - Record the depths of both the upper and lower
boundary for each horizon; specify units (centimeters preferred); e.g., 1524 cm. Begin (zero datum) at the ground surface1, which is not necessarily
the mineral surface. (NOTE: Prior to 1993, the zero datum was at the top of
the mineral surface, except for thick organic layers such as a peat or muck.
5/13/98
2-4
USDA - NRCS
Organic horizons were recorded as above and mineral horizons recorded as
below, relative to the mineral surface.) Example:
Zero Datum for the same horizons
At Present:
Oe 0 - 5 cm, A 5 - 15 cm, E 15 - 24 cm
Before 1993: Oe 5 - 0 cm, A 0 - 10 cm, E 10 - 19 cm
1
Conventionally, the “soil surface” is considered to be the top boundary of
the first layer that can support plant / root growth. This equates to:
a) (for bare mineral soil) the air/fine earth interface;
b) (for vegetated mineral soil) the upper boundary of the first layer that
can support root growth;
c) (for organic mantles) the same as b) but excludes freshly fallen plant
litter, and includes litter that has compacted and begun to decompose;
e.g., Oi horizon;
d) (for submerged soil) the same as b) but refers to the water/soil contact
and extends out from shore to the limit of emergent, rooted plants;
e) (for rock mulches; e.g., desert pavement, scree) the same as a)
unless the areal percentage of surface rock coverage is greater than
80%, the top of the soil is the mean height of the top of the rocks.
HORIZON THICKNESS - Record the average thickness and range in
thickness of horizon; e.g., 15 cm (12 - 21 cm).
HORIZON BOUNDARY - Record Distinctness and Topography of horizon
boundary. Distinctness is the distance through which one horizon grades
into another. Topography is the lateral undulation and continuity of the
boundary between horizons. A complete example is: clear, wavy, or C,W.
Distinctness Distinctness
Class
Very Abrupt
Abrupt
Clear
Gradual
Diffuse
USDA - NRCS
PDP
--A
C
G
D
Code
NASIS
V
A
C
G
D
2-5
Criteria:
thickness
< 0.5 cm
0.5 to < 2 cm
2 to < 5 cm
5 to < 15 cm
15 cm
5/13/98
Topography - Cross-sectional shape of the contact between horizons.
Topography
Smooth
Wavy
Irregular
Broken
Code
S
W
I
B
Criteria
Planar with few or no irregularities
Width of undulation is > than depth
Depth of undulation is > than width
Discontinuous horizons; discrete but
intermingled, or irregular pockets
Wavy
Smooth
A
A
B
B
Irregular
Broken
A
A
B
B
5/13/98
E
Bt
2-6
USDA - NRCS
SOIL COLOR
DECISION FLOWCHART FOR DESCRIBING SOIL COLORS - Use the
following chart to decide how and with which data elements the color
patterns of a soil or soil feature should be described.
NOTE: Reduced Matrix color is described as a Matrix Color and in the
associated “(Soil Color) - Location or Condition Described Table”.
(SOIL) MATRIX COLOR - Record Color(s), (Soil Color) Moisture State,
Location or Condition. (In PDP, also record Percent of Horizon, if more
than one matrix color is described.)
USDA - NRCS
2-7
5/13/98
(Soil) Matrix Color - (Soil) Color - Use Munsell notation (Hue,
Value, Chroma); e.g., 10YR 3/2. Neutral Gley colors are written as
chroma of zero (0); e.g, N 4/0. Other gley colors use appropriate
notation (see Munsell Gley pages; e.g., 5GY 6/1). For narrative
descriptions (Soil Survey Reports, Official Series Descriptions) both the
verbal name and the Munsell notation are given; e.g., dark brown,
10YR 3/3.
(Soil) Matrix Color - Moisture State - Record the moisture condition of
the soil described; e.g., moist. (Not to be confused with Soil Water
State.)
Moisture State
Dry
Moist
Code
D
M
(Soil) Matrix Color - Location or Condition - Record pertinent
circumstances of the color described.
Color Location or Condition
PDP
Code
NASIS
COLOR LOCATION
Interior (within ped)
1
Exterior (ped surface)
2
COLOR, MECHANICAL CONDITION
Broken Face
8
Crushed
3
Rubbed (used only with Organic Matter)
9
COLOR, REDOXIMORPHIC CONDITION
Oxidized 1
5
Reduced 2
--COLOR, INTRICATE MULTICOLORED PATTERN
Variegated 3
--1
2
3
5/13/98
IN
EX
BF
CR
RU
OX
RE
VA
Soil that is reduced in situ, but oxidizes (changes color) after
extraction and exposure to air. A mineral example is vivianite.
NOTE: Not used for soil that’s normally oxidized in-place. For
indicators of reduction see Redoximorphic Features.
Color immediately after extraction from a reduced environment,
prior to oxidation; e.g., FeS. Also used to record Reduced
Matrix.
Color pattern is too intricate (banded or patchy) with numerous,
diverse colors to credibly identify dominant matrix colors.
2-8
USDA - NRCS
MOTTLES - Describe mottles (areas of color that differ from the matrix
color). These colors are commonly lithochromic or lithomorphic (attributes
retained from the geologic source rather than from pedogenesis; e.g., gray
shale). Mottles exclude: Redoximorphic Features (RMF) and Ped & Void
Surface Features; e.g., clay films. Record Quantity Class (in NASIS/PDP,
estimate a numerical value “Percent of Horizon Area Covered”), Size,
Contrast, Color, and Moisture State (D or M). Shape is an optional
descriptor (use the “Concentrations - Shape Table”). A complete example is:
few, medium, distinct, reddish yellow, moist, irregular mottles or f, 2, d, 7.5
YR 7/8, m, z, mottles.
Mottles - Quantity (Percent of Area Covered) Quantity
Class
Few
Common
Many
Code
Conv NASIS
f
%
c
%
m
%
Criteria:
range in percent
< 2% of surface area
2 to < 20% of surface area
20% of surface area
Mottles - Size - Record mottle size class. Use length if it’s greater than
2 times the width; use width if the length is less than two times the
width. Length is the greater of the two dimensions. (New size classes
to be consistent with the new RMF size classes.)
Size Class
Fine
Medium
Coarse
Very Coarse
Extremely Coarse
USDA - NRCS
Code
1
2
3
4
5
2-9
Criteria
< 2 mm
2 to < 5 mm
5 to < 20 mm
20 to < 76 mm
76 mm
5/13/98
5/13/98
2-10
USDA - NRCS
Mottles - Contrast - Record the color difference between the mottle
and the dominant matrix color. Use this table or the following chart to
express the difference.
Contrast
Class
1
2
Code
Faint 2
Distinct
F
D
Prominent
P
Difference in Color
Between Matrix and Mottle
Hue 1
Value
Chroma
1
same page 0 to 2
and
same page > 2 to < 4
and
<4
or
<4
and
> 1 to < 4
2
1
1 page
and
4
same page 4
or
1 page
>2
or
>1
2 pages 0
0
or
One Munsell Color Book page = 2.5 hue units. Table contents
compiled from material in or intended by the Soil Survey Manual
(Soil Survey Staff, 1993).
Faint also includes mottles or RMFs that are similar in color to the
matrix that have both low (e.g., 3) value and chroma, and differ
by up to 2.5 units (one page) of hue.
Mottles - Color - Use standard Munsell notation of hue, value,
chroma; e.g., 5 YR 4/4 (for reddish brown).
Mottles - Moisture State - Record the moisture condition of the mottle
(not to be confused with soil water state); e.g., moist.
Moisture State
Dry
Moist
Code
D
M
Mottles - Shape (optional) - Use “Concentrations - Shape Table”; e.g.,
irregular.
NOTE: In PDP, Location (optional), and Hardness (optional) can be
described. Use the choices in the appropriate “Redoximorphic
Features Table”.
USDA - NRCS
2-11
5/13/98
5/13/98
2-12
USDA - NRCS
REDOXIMORPHIC FEATURES (RMF) DISCUSSION
Redoximorphic Features (RMF) are a color pattern in a soil due to loss
(depletion) or gain (concentration) of pigment compared to the matrix color,
formed by oxidation / reduction of Fe and/or Mn coupled with their removal,
translocation, or accrual; or a soil matrix color controlled by the presence of
Fe+2. The composition and process of formation for a soil color or color
pattern must be known or inferred before describing it as a RMF. Because of
this inference, RMF are described separately from other mottles,
concentrations; e.g., salts; or compositional features; e.g., clay films. RMF
generally occur in one or more of these settings:
a. In the soil matrix, unrelated to surfaces of peds or pores.
b. On or beneath the surfaces of peds.
c. As filled pores, linings of pores, or beneath the surfaces of pores.
RMFs include the following:
1. Redox Concentrations - Localized zones of enhanced pigmentation
due to an accrual of, or a phase change in, the Fe-Mn minerals; or are
physical accumulations of Fe-Mn minerals. NOTE: Iron concentrations
may be either Fe+3 or Fe+2. Types of redox concentrations are:
a. Masses - Noncemented bodies of enhanced pigmentation that have
a redder or blacker color than the adjacent matrix.
b. Nodules or Concretions - Cemented bodies of Fe-Mn oxides.
2. Redox Depletions - Localized zones of “decreased” pigmentation that
are grayer, lighter, or less red than the adjacent matrix. Redox
depletions include, but are not limited to, what were previously called
“low chroma mottles” (chroma 2). Depletions with chroma 2 are
used to define aquic conditions in Soil Taxonomy and are used
extensively in the field to infer occurrence and depth of saturation in
soils. Types of redox depletions are:
a. Iron Depletions - Localized zones that have one or more of the
following: a yellower, greener, or bluer hue; a higher value; or a
lower chroma than the matrix color. Color value is normally 4.
Loss of pigmentation results from the loss of Fe and/or Mn. Clay
content equals that in the matrix.
b. Clay Depletions - Localized zones that have either a yellower hue, a
higher value, or a lower chroma than the matrix color. Color value is
normally 4. Loss of pigmentation results from a loss of Fe and/or
Mn and clay. Silt coats or skeletans commonly form as depletions
but can be non-redox concentrations, if deposited as flow material in
pores or along faces of peds.
USDA - NRCS
2-13
5/13/98
3. Reduced Matrix - A soil horizon that has an in situ matrix chroma 2
due to the presence of Fe+2. Color of a sample becomes redder or
brighter (oxidizes) when exposed to air. The color change usually
occurs within 30 minutes. A 0.2% solution of , '- dipyridyl dissolved in
1N ammonium acetate (NH4OAc) pH 7 can verify the presence of Fe+2 in
the field (Childs, 1981).
NOTE: Use of RMF alters the traditional sequence for describing soil color
(see the “Decision Flowchart for Describing Colors for Soil Matrix and Soil
Features”). RMF are described separately from other color variations or
concentrations. Mottles (color variations not due to loss or accrual of Fe-Mn
oxides; e.g., variegated weathered rock) are still described under Soil Color.
A Reduced Matrix is recorded as a RMF and as “reduced” in Soil Color Location or Condition Described.
REDOXIMORPHIC FEATURES
Record Kind, Quantity (percent of area covered), Size, Contrast, Color,
Moisture State, Shape, Location, Hardness, and Boundary. A complete
example is: common, medium, prominent, black Iron-Manganese nodules,
moist, spherical In the matrix, hard, sharp or c, 2, p, 5 YR 2.5/1, FMM, M, o,
h, s.
REDOXIMORPHIC FEATURES - KIND Kind
Code
PDP
Kind
NASIS
Code
PDP
REDUCED MATRIX (chroma 2 primarily from Fe+2)
Reduced Matrix
--RMX
REDOX DEPLETIONS (loss of pigment or material)
Clay Depletions
A3
CLD
Iron Depletions
F5
(includes depletion
halo)
Chroma > 2
--HCD
Chroma > 2
--REDOX CONCENTRATIONS (accumulated pigment, material)
Masses 1 (noncemented)
Iron (Fe+3) 3, 4, 5
F2
F3M
Iron-Manganese 3, 4, 5
M2
Iron (Fe+2) 2
--F2M
Manganese 4, 5
M8
Nodules 1 (cemented; no layers, crystals not visible at 10X)
Ironstone
F4
FSN
Iron-Manganese 4
M5
Plinthite
F1
PLN
Concretions 1 (cemented; distinct layers, crystals not visible)
Iron-Manganese 4
M3
5/13/98
2-14
NASIS
FED
HFD
FMM
MNM
FMN
FMC
USDA - NRCS
Surface Coats / Films or Hypocoats
Manganese (mangans: black, very thin, exterior films)
Ferriargillans (Fe+3 stained clay film)
1
2
3
4
5
MNF
FEF
See discussion under Concentrations for definitions.
A concentration of reduced iron Fe+2; e.g., FeS.
A concentration of oxidized iron Fe+3; e.g., hematite, (formerly
described as reddish mottles).
Iron and Mn commonly occur in combination and field identification of
distinct phases is difficult. Use Mn masses only for those that are at
least Slightly Effervescent with H202. Describe nodules and
concretions as Iron-Manganese unless colors are unambiguous.
Suggested, color guidelines for field description of Fe vs. Mn Masses:
Color of Concentration
Value
Chroma
2
2
>2&4
>2&4
>4
>4
6
M6
I6
Dominant Composition
Mn
Fe & Mn
Fe
In PDP, these features (codes) are recorded under Coat - Kind.
REDOXIMORPHIC FEATURES - QUANTITY (Percent of Area Covered) Class
Few
Common
Many
USDA - NRCS
Conv.
f
c
m
Code
NASIS
#
#
#
2-15
Criteria: Percent of
Surface Area Covered
<2
2 to < 20
20
5/13/98
REDOXIMORPHIC FEATURES - SIZE - See size class graphic under either
Mottles or Concentrations.
Size Class
Fine
Medium
Coarse
Very Coarse
Extremely Coarse
Code
1
2
3
4
5
Criteria
< 2 mm
2 to < 5 mm
5 to < 20 mm
20 to < 76 mm
76 mm
REDOXIMORPHIC FEATURES - CONTRAST - Use “Mottle - Contrast
Table” or “Mottle - Contrasts Chart”; e.g., Prominent or p.
REDOXIMORPHIC FEATURES - COLOR - Use standard Munsell notation
from the “Soil Color Section”; e.g., light brownish gray or 2.5Y 6/2.
REDOXIMORPHIC FEATURES - MOISTURE STATE - Describe the
moisture condition of the Redoximorphic Feature (use “Soil Color - Moisture
State Table”); e.g., Moist (M) or Dry (D).
REDOXIMORPHIC FEATURES - SHAPE - Describe the shape of the
redoximorphic feature (use “Concentrations - Shape Table”); e.g., Spherical
(O).
REDOXIMORPHIC FEATURES - LOCATION - Describe the location(s) of
the Redoximorphic Feature within the horizon (use “Concentrations Location Table”); e.g., In the matrix (R1).
REDOXIMORPHIC FEATURES - HARDNESS - Describe the hardness of
the Redoximorphic Feature (use cementation classes from the “Consistence
- Rupture Resistance for Blocks / Peds / Clods Table”);
e.g., Strongly Cemented (ST).
REDOXIMORPHIC FEATURES - BOUNDARY - The gradation between the
Redoximorphic Feature and the adjacent matrix (use “Concentrations Boundary Table”); e.g., Sharp (S).
5/13/98
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USDA - NRCS
CONCENTRATIONS DISCUSSION
Concentrations are soil features that form by accumulation of material during
pedogenesis. Dominant processes involved are chemical dissolution/
precipitation; oxidation and reduction; and physical and/or biological removal,
transport, and accrual. Types of concentrations (modified from Soil Survey
Staff, 1993) include the following:
1.
Finely Disseminated Materials are physically small precipitates (e.g.,
salts, carbonates) dispersed throughout the matrix of a horizon. The
materials cannot be readily seen (10X lens), but can be detected by a
chemical reaction (e.g., effervescence of CaCO3 by HCl) or other proxy
indicators.
2.
Masses are noncemented (“Rupture Resistance Cementation Class” of
Extremely Weakly Cemented or less) bodies of accumulation of various
shapes that cannot be removed as discrete units, and do not have a
crystal structure that is readily discernible in the field (10X hand lens).
This includes finely crystalline salts and Redox Concentrations that do
not qualify as nodules or concretions.
3.
Nodules are cemented (Very Weakly Cemented or greater) bodies of
various shapes (commonly spherical or tubular) that can be removed
as discrete units from soil. Crystal structure is not discernible with a
10X hand lens.
4.
Concretions are cemented bodies (Very Weakly Cemented or greater)
similar to nodules, except for the presence of visible, concentric layers
of material around a point, line, or plane. The terms “nodule” and
“concretion” are not interchangeable.
5.
Crystals are macro-crystalline forms of relatively soluble salts (e.g.,
halite, gypsum, carbonates) that form in situ by precipitation from soil
solution. The crystalline shape and structure is readily discernible in
the field with a 10X hand lens.
6.
Biological Concentrations are discrete bodies accumulated by a
biological process (e.g., fecal pellets), or pseudomorphs of biota or
biological processes (e.g., insect casts).
USDA - NRCS
2-17
5/13/98
General conventions for documenting various kinds of Concentrations:
Type of Distribution
Finely Disseminated (not
visible)
Masses, Nodules,
Concretions, Crystals,
Biological Features
Continuous Cementation
Documentation
Horizon Suffix
Redoximorphic
Features, or
Concentrations
Terms in Lieu of
Texture
Examples
Carbonates (Bk)
Salts (Bz, Bn)
Mn nodules
Fe concretions
Insect casts
Duripan
Petrocalcic
Finely Disseminated
Masses
(not visible; reaction)
( < Very Weakly Cemented)
Nodules
( ≥ Very Weakly Cemented)
Concretions
Crystals
( ≥ Very Weakly Cemented)
crosssectional
view
CONCENTRATIONS
Record Kind, Quantity (percent of area covered), Size, Contrast, Color,
Moisture State, Shape, Location, Hardness, and Boundary. A complete
example is: many, fine, prominent, white, moist, cylindrical, carbonate
nodules in the matrix, moderately cemented, clear or m, 1, p, 10YR 8/1, M, c,
CAN, MAT, M, c.
CONCENTRATIONS - KIND - Identify the composition and the physical state
of the concentration in the soil. NOTE: Table sub-headings (e.g., Masses)
are a guide to various physical states of materials. Materials with similar or
identical chemical compositions may occur in multiple physical states (under
several sub-headings); e.g., salt masses and salt crystals.
5/13/98
2-18
USDA - NRCS
CONCENTRATIONS (NON-REDOX) (accumulations of material)
Kind
Code
Kind
Code
PDP NASIS
PDP
NASIS
MASSES (noncemented; crystals not visible with 10X hand lens)
Barite (BaSO4)
B2
BAM Gypsum (CaSO42H20)
G2
GYM
Carbonates
K2
CAM Salt
H2
SAM
(Ca, Mg, NaCO3)
(NaCl, Na-Mg Sulfates)
Clay Bodies
A2
CBM Silica
S2
SIM
Gypsum (Nests)
G3
GNM
NODULES (cemented; non-crystalline at 10X, no layers)
Carbonates 1
C4
CAN Gibbsite (Al2O3)
E4
GBN
Durinodes (SiO2)
S4
DNN Opal
S1
OPN
CONCRETIONS (cemented; non-crystalline at 10X, distinct layers)
Carbonates 1
C3
CAC Silica
S3
SIC
Gibbsite
E3
GBC Titanium Oxide
--TIC
CRYSTALS (crystals visible with 10X hand lens)
Barite (BaSO4)
B1
BAX Gypsum (CaSO42H20)
G1
GYX
Calcite (CaCO3)
C1
CAX Salt
H1
SAX
(NaCl, Na-Mg Sulfates)
BIOLOGICAL CONCENTRATIONS (byproducts or pseudomorphs)
Fecal Pellets
--FPB Shell Fragments
--SFB
(terrestrial or aquatic)
ICB Sponge Spicules 3
Insect Casts 2
T3
--SSB
Plant Phytoliths 3
--PPB Worm Casts 2
T2
WCB
(plant opal)
Root Sheaths
--RSB
1
2
3
Also known as loess kinchen, loess puppies, etc.
Worm casts are ovoid, fecal pellets excreted by earthworms. Insect
casts are cemented (e.g., CaCO3) molds of insect bodies or burrows.
May require magnification > 10X to be observed.
USDA - NRCS
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5/13/98
CONCENTRATIONS - QUANTITY (PERCENT OF AREA COVERED) Class
Few
Common
Many
Conv.
f
c
m
Code
NASIS
#
#
#
Criteria: % of
Surface Area Covered
<2
2 to < 20
20
CONCENTRATIONS - SIZE - Use “RMF’s” and “Mottle Size Classes”. (See
graphic on next page.)
Size Class
Fine
Medium
Coarse
Very Coarse
Extremely Coarse
Code
1
2
3
4
5
Criteria
< 2 mm
2 to < 5 mm
5 to < 20 mm
20 to < 76 mm
76 mm
CONCENTRATIONS - CONTRAST - Use “Mottle - Contrast Table” or “Mottle
- Contrast Chart”; e.g., distinct.
CONCENTRATIONS - COLOR - Use standard Munsell notation; e.g., 7.5
YR 8/1.
CONCENTRATIONS - MOISTURE STATE - Use “Soil Color - Moisture State
Table”; e.g., Moist (M) or Dry (D).
5/13/98
2-20
USDA - NRCS
USDA - NRCS
2-21
5/13/98
CONCENTRATIONS - SHAPE Shape
Code
Criteria
NASIS
C
C
tubular & elongated bodies; e.g., filled
worm holes and insect burrows
D
D
tubular, elongated, branched bodies;
e.g., pipestems (root pseudomorphs)
Z
I
bodies of non-repeating spacing or
shape
P
P
relatively thin, tabular sheets, lenses;
e.g., lamellae
--R
crudely interlocking bodies with similar
spacing; e.g., plinthite
O
S
well-rounded to crudely spherical
bodies; e.g., Fe / Mn “shot”
T
T
thin (e.g., < 1 mm diam.) elongated
filaments; generally not dendritic; e.g.,
very fine CaCO3 stringers
PDP
Cylindrical
Dendritic
Irregular
Platy
Reticulate
Spherical 1
Threads
1
Called Rounded in PDP.
Examples of Mottles, Concentrations, and RMF Shapes
Cylindrical
(e.g. filled
worm holes)
Dendritic
(e.g. branched root
pseudomorphs)
Irregular
Platy
(e.g. lamellae)
Spherical
(e.g. Fe/Mn shot)
Threads
(e.g. very fine
CaCO 3 stringers)
Reticulate
(e.g. plinthite)
CONCENTRATIONS - LOCATION - (Also used for Redoximorphic
Features.) Describe the location(s) of the concentration (or depletion for
RMF’s) within the horizon. Historically called Concentrations Distribution.
5/13/98
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USDA - NRCS
Location
Code
NASIS
MATRIX (in soil matrix; not associated with, peds or pores)
In the matrix (not associated with peds/pores)
--MAT
In matrix around depletions
--MAD
In matrix around concentrations
--MAC
Throughout (e.g., finely disseminated carbonates)
T
TOT
PEDS (on or associated with faces of peds)
Between peds
P
BPF
Infused into the matrix along faces of peds (hypocoats) 1 --MPF
On faces of peds (all orientations)
--APF
On horizontal faces of peds
--HPF
On vertical faces of peds
--VPF
PORES (in pores, or associated with surfaces along pores)
On surfaces along pores
--SPO
Infused into the matrix adjacent to pores (hypocoats) 1
--MPO
Lining pores 1
--LPO
OTHER
In cracks
C
CRK
Top of horizon
M
TOH
Around rock fragments
S
ARF
On bottom of rock fragments (e.g., pendants)
--BRF
PDP
1
See illustration under Ped and Void Surface Features - Kind.
CONCENTRATIONS - HARDNESS - Describe the relative force required to
crush the concentration body. Record the appropriate Rupture Resistance Cementation Class (see “Rupture Resistence Table”); e.g., Moderately
Cemented (exclude the Non-Cemented class). NOTE: PDP doesn’t
recognize the Moderately Hard class, dry nor moist (= Very Weakly
Cemented class).
CONCENTRATIONS - BOUNDARY - The gradation between feature and
matrix.
Class
Sharp
Code
S
Clear
C
Diffuse
D
USDA - NRCS
Criteria
Color changes in < 0.1 mm; change is abrupt
even under a 10X hand lens.
Color changes within 0.1 to < 2 mm; gradation is
visible without 10X lens.
Color changes in 2 mm; gradation is easily
visible without 10X hand lens.
2-23
5/13/98
PED & VOID SURFACE FEATURES
These features are coats/films, hypocoats, or stress features formed by
translocation and deposition, or shrink-swell processes on or along surfaces.
Describe Kind, Amount Class (percent in NASIS and PDP), Distinctness,
Location, and Color (dry or moist). An example is: many, faint, brown
10YR 4/6 (Moist), clay films on all faces of peds or m, f, 10YR 4/6 (M), CLF,
PF.
PED & VOID SURFACE FEATURES - KIND (non-redoximorphic) Kind
Code
Field Criteria
PDP NASIS
COATS, FILMS (exterior, adhered to surface)
Carbonate Coats
K
CAF off-white, effervescent with HCl
Silica (silans, opal)
-SIF off-white, noneffervesent with HCl
Clay Films (Argillans)
T
CLF waxy, exterior coats
Clay Bridging
D
BRF “wax” between grains
Ferriargillans
see Fe+3 stained clay film
Described as RMF - Kind
RMFs
Gibbsite Coats (sesquan)
G
GBF AlOH3, off-white, noneffervescent
with HCl
Manganese (mangans)
see black, thin films effervescent with
Described as RMF - Kind
RMFs H2O2
Organic Stains
-OSF dark organic films
Organoargillans
O
OAF dark, organic stained clay films
Sand Coats
Z
SNF separate grains visible with 10X
Silt Coats 1
R
SLF separate grains not visible at 10X
Skeletans 2 (sand or silt)
S
SKF clean sand or silt grains as coats
Skeletans on argillans
A
SAF clean sand or silt over clay coats
HYPOCOATS 3 (A stain infused beneath a surface.)
STRESS FEATURES (exterior face)
Pressure faces
P
PRF look like clay films; sand grains
(i.e. stress cutans)
uncoated
Slickensides
K
SS slip face; grooves, striations, glossy
or shiny
1
2
3
Individual silt grains are not discernible with a 10X lens. Silt coats
occur as a fine, off-white, noneffervescent, “grainy” coat on surfaces.
Skeletans are (pigment) stripped grains > 2 m and < 2 mm (Brewer,
1976). Preferably describe either silt coats (grains not discernible with
10X lens), or sand coats (grains discernible with 10X lens).
Hypocoats, as used here, are field-scale features commonly
expressed only as Redoximorphic Features. Micromorphological
hypocoats include non-redox features (Bullock, et al., 1985).
5/13/98
2-24
USDA - NRCS
Peds
Pores
General
COATS/
FILMS
On
Surface
Argillans
sand grains "waxed" over
Skeletans
Clay
Bridging
Sand
Grain
Sand
Grain
HYPOCOATS
Below
Surface
Pressure Face
Slickensides
sand grains stand clear
striations, glossy sheen
STRESS
FEATURES
USDA - NRCS
2-25
5/13/98
PED & VOID SURFACE FEATURES - AMOUNT - Estimate the relative
percent of the visible surface area that a ped-surface feature occupies in a
horizon. (See graphic on next page.) In PDP & NASIS, record the estimate
as a numeric percent; e.g., 20%.
Amount
Class
Very Few
Few
Common
Many
Very Many
Code
Conv.
NASIS
vf
%
f
%
c
%
m
%
vm
%
Criteria:
percent of surface area
< 5 percent
5 to < 25 percent
25 to < 50 percent
50 to < 90 percent
90 percent
PED & VOID SURFACE FEATURES - CONTINUITY (Obsolete in NRCS) Replaced by Ped & Void Surface Feature - Amount in PDP.
Continuity Class
Continuous
Discontinuous
Patchy
5/13/98
Code (Conv.)
C
D
P
2-26
Criteria: Features Occur As
Entire Surface Cover
Partial Surface Cover
Isolated Surface Cover
USDA - NRCS
PED & VOID SURFACE FEATURES - DISTINCTNESS - The relative extent
to which a ped surface feature visually stands out from adjacent material.
Distinctness
Class
Faint
Code
Criteria:
F
Visible with magnification only (10X hand
lens); little contrast between materials.
Visible without magnification; significant
contrast between materials.
Markedly visible without magnification;
sharp visual contrast between materials.
Distinct
D
Prominent
P
PED & VOID SURFACE FEATURES - LOCATION - Specify where pedsurface features occur within a horizon; e.g., Between sand grains.
Location
PDP
PEDS
On Bottom Faces of Peds
On Top Faces of Peds
On Vertical Faces of Peds
On All Faces of Peds (vertical & horizonal)
On Tops of Soil Columns
OTHER (NON-PED)
Between Sand Grains (bridging)
On Surfaces Along Pores
On Surfaces Along Root Channels
On Concretions
On Nodules
On Rock Fragments
On Top Surfaces of Rock Fragments
On Bottom Surfaces of Rock Fragments
1
Code
NASIS
L1
U1
V
P
C
BF
TF
VF
PF
TC
B
I1
I1
O
N
R
U1
L1
BG
SP
SC
CC
NO
RF
TR
BR
Codes are repeated because these choices are combined in PDP.
PED & VOID SURFACE FEATURES - COLOR - Use standard Munsell
notation (hue, value, chroma) to record feature color.
USDA - NRCS
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5/13/98
(SOIL) TEXTURE
This is the numerical proportion (percent by weight) of sand, silt, and clay in
a soil. Sand, silt, and clay content is estimated in the field by hand (or
quantitatively measured in the office/lab by hydrometer or pipette) and then
placed within the texture triangle to determine Texture Class. Estimate the
Texture Class; e.g., sandy loam; or Subclass; e.g., fine sandy loam of the
fine earth (< 2 mm) fraction, or choose a Term in Lieu of Texture; e.g.,
gravel. If appropriate, use a Textural Class Modifier; e.g., gravelly silt
loam.
NOTE: Soil Texture encompasses only the fine earth fraction (< 2 mm).
Particle Size Distribution (PSD) encompasses the whole soil, including
both the fine earth fraction (< 2 mm) and rock fragments (> 2 mm).
TEXTURE CLASS Texture Class
Coarse Sand
Sand
Fine Sand
Very Fine Sand
Loamy Coarse Sand
Loamy Sand
Loamy Fine Sand
Loamy Very Fine Sand
Coarse Sandy Loam
Sandy Loam
Fine Sandy Loam
Very Fine Sandy Loam
Loam
Silt Loam
Silt
Sandy Clay Loam
Clay Loam
Silty Clay Loam
Sandy Clay
Silty Clay
Clay
5/13/98
Code
Conv.
cos
s
fs
vfs
lcos
ls
lfs
lvfs
cosl
sl
fsl
vfsl
l
sil
si
scl
cl
sicl
sc
sic
c
2-28
NASIS
COS
S
FS
VFS
LCOS
LS
LFS
LVFS
COSL
SL
FSL
VFSL
L
SIL
SI
SCL
CL
SICL
SC
SIC
C
USDA - NRCS
TEXTURE MODIFIERS - Conventions for using “Rock Fragment Texture
Modifiers” and for using textural adjectives that convey the “% volume”
ranges for Rock Fragments - Size & Quantity.
Fragment Content
Rock Fragment Modifier Usage
% By Volume
< 15
No texture adjective is used (noun only; e.g., loam).
15 to < 35
Use adjective for appropriate size; e.g., gravelly.
35 to < 60
Use “very” with the appropriate size adjective; e.g.,
very gravelly.
60 to < 90
Use “extremely” with the appropriate size adjective;
e.g., extremely gravelly.
90
No adjective or modifier. If 10% fine earth, use
the appropriate noun for the dominant size class;
e.g., gravel. Use Terms in Lieu of Texture.
USDA - NRCS
2-29
5/13/98
5/13/98
2-30
USDA - NRCS
References for Table Comparing Particle Size Systems
1
Soil Survey Staff. 1995. Soil survey laboratory information manual.
USDA - Natural Resources Conservation Service, Soil Survey
Investigations Report No. 45, Version 1.0, National Soil Survey Center,
Lincoln, NE. 305 p.
2
International Soil Science Society. 1993. In: Soil Survey Manual. Soil
Survey Staff, USDA - Soil Conservation Service, Agricultural Handbook
No. 18, U.S. Gov. Print. Office, Washington, D.C. 503 p.
3
ASTM. 1993. Standard classification of soils for engineering purposes
(Unified Soil Classification System). ASTM designation D2487-92. In:
Soil and rock; dimension stone; geosynthetics. Annual book of ASTM
standards - Vol. 04.08.
4
ASSHTO. 1986a. Recommended practice for the classification of soils
and soil-aggregate mixtures for highway construction purposes.
ASSHTO designation M145-82. In: Standard specifications for
transportation materials and methods of sampling and testing; Part 1:
Specifications (14th ed.). American Association of State Highway and
Transportation Officials, Washington, D.C.
5
ASSHTO. 1986b. Standard definitions of terms relating to subgrade,
soil-aggregate, and fill materials. ASSHTO designation M146-70 (1980).
In: Standard specifications for transportation materials and methods of
sampling and testing; Part 1: Specifications (14th ed.). American
Association of State Highway and Transportation Officials,
Washington, D.C.
6
Ingram, R.L. 1982. Modified Wentworth scale. In: Grain-size scales.
AGI Data Sheet 29.1. In: Dutro, J.T., Dietrich, R.V., and Foose, R.M.
1989. AGI data sheets for geology in the field, laboratory, and office, 3rd
edition. American Geological Institute, Washington, D.C.
USDA - NRCS
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5/13/98
TEXTURE MODIFIERS - (adjectives)
ROCK
Code
Criteria: Percent (By Volume)
PDP /
FRAGMENTS:
of Total Rock Fragments and
Conv.
NASIS
Size & Quantity 1
Dominated By (name size): 1
HARD ROCK FRAGMENTS (> 2 mm)
15% but < 35% gravel
Gravelly
GR
GR
15% but < 35% fine gravel
Fine Gravelly
FGR
GRF
15% but < 35% med. gravel
Medium Gravelly
MGR
GRM
15% but < 35% coarse gravel
Coarse Gravelly
CGR
GRC
35% but < 60% gravel
Very Gravelly
VGR
GRV
60% but < 90% gravel
Extremely Gravelly
XGR
GRX
15% but < 35% cobbles
Cobbly
CB
CB
35% but < 60% cobbles
Very Cobbly
VCB
CBV
60% but < 90% cobbles
Extremely Cobbly
XCB
CBX
15% but < 35% stones
Stony
ST
ST
35% but < 60% stones
Very Stony
VST
STV
60% but < 90% stones
Extremely Stony
XST
STX
15% but < 35% boulders
Bouldery
BY
BY
35% but < 60% boulders
Very Bouldery
VBY
BYV
60% but < 90% boulders
Extremely Bouldery
XBY
BYX
15% but < 35% channers
Channery
CN
CN
35% but < 60% channers
Very Channery
VCN
CNV
60% but < 90% channers
Extremely Channery
XCN
CNX
15% but < 35% flagstones
Flaggy
FL
FL
35% but < 60% flagstones
Very Flaggy
VFL
FLV
60% but < 90% flagstones
Extremely Flaggy
XFL
FLX
PARA (SOFT) ROCK FRAGMENTS (> 2 mm) 2, 3
Parabouldery
PBY
PBY
(same criteria as bouldery)
Very Parabouldery
VPBY
PBYV
(same criteria as very bouldery)
Extr. Parabouldery
XPBY
PBYX
(same criteria as ext. bouldery)
etc.
etc.
etc.
(same criteria as non -para)
1
2
The “Quantity” modifier (e.g., very) is based on the total rock fragment
content. The “Size” modifier (e.g., cobble) is based on the largest,
dominant fragment size. For a mixture of sizes (e.g., gravel and
stones), the smaller size must exceed 2X the amount of the larger
size to be named (e.g., 30% gravel and 14% stones = very gravelly;
20% gravel and 14% stones = stony).
Use “Para” prefix if the rock fragments are soft (i.e., meet criteria for
“para”). [Rupture Resistance - Cementation Class < Moderately
Cemented, and do not slake (24 hrs in water).]
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USDA - NRCS
3
For “Para” codes, add “P” to “Size” and “Quantity” code terms.
Precedes noun codes and follows quantity adjectives, e.g.,
paragravelly = PGR; very paragravelly = VPGR.
COMPOSITIONAL TEXTURE MODIFIERS 1 - (adjectives)
Types
Code
NASIS
Criteria:
PDP
VOLCANIC
Ashy
--
Hydrous
--
Medial
--
ORGANIC SOILS
Grassy 2
-Herbaceous 2
-Mossy 2
-Mucky
MK
Peaty
PT
Woody 2
-LIMNIC MATERIALS
Coprogenous
-Diatomaceous
-Marly
-OTHER
Gypsiferous
-Permanently
PF
Frozen
1
2
ASHY Neither hydrous nor medial and 30% of the
< 2 mm fraction is 0.02 to 2.00 mm in size of
which 5% is volcanic glass
HYDR Andic properties and with field moist 15 bar
water content 100% of the dry weight
MEDL Andic properties and with field moist 15 bar
water content 30% to < 100% of the dry
weight or 12% water content for air-dried
samples
GS
HB
MS
MK
PT
WD
OM > 15% (vol.) grassy fibers
OM > 15% (vol.) herbaceous fibers
OM > 15% (vol.) moss fibers
Mineral soil > 10% OM and < 17% fibers
Mineral soil > 10% OM with > 17% fibers
OM 15% (vol.) wood pieces or fibers
COP
DIA
MR
GYP
PF
15% (weight) gypsum
e.g., Permafrost
Compositional Texture Modifiers can be used with the Soil Texture
Name; e.g., gravelly ashy loam or mossy peat. For definitions and
usage of Compositional Texture Modifiers, see the National Soil
Survey Handbook - Part 618 (Soil Survey Staff, 1996c).
Used only with Histosols, histic epipedons, or mucky peats and peats.
USDA - NRCS
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5/13/98
TERMS USED IN LIEU OF TEXTURE - (nouns)
Terms Used in Lieu
of Texture
SIZE (HARD ROCKS)
Gravel
Cobbles
Stones
Boulders
Channers
Flagstones
SIZE (SOFT ROCKS)
Paragravel
Paracobbles
Parastones
Paraboulders
Parachanners
Paraflagstones
COMPOSITION
Cemented / Consolidated:
Duripan (silica cement)
Ortstein (organic with Fe and Al cement)
Petrocalcic (carbonate cement)
Petroferric (Fe cement)
Petrogypsic (gypsum cement)
Placic Horizon (thin layer cemented by Fe & Mn)
Unweathered Bedrock (unaltered)
Weathered Bedrock (altered; e.g., some Cr
horizons)
Organics:
Highly Decomposed Plant Material (Oa) 1
Moderately Decomposed Plant Material (Oe) 1
Slightly Decomposed Plant Material (Oi) 1
Muck 2 (Oa)
Mucky Peat 2 (Oe)
Peat 2 (Oi)
Other:
Finely Stratified (contrasting textures)
Ice (permanently frozen) 3, 4
Water (permanent) 3, 4
1
2
3
4
Code
NASIS
PDP
G
CB
ST
B
---
G
CB
ST
BY
CN
FL
-------
PGR
PCB
PST
PBY
PCN
PFL
------UWB
WB
DUR
OR
PC
PF
PGP
PL
UB
WB
-------------
HPM
MPM
SPM
MUCK
MPT
PEAT
----
FS
IC
W
Use only with mineral soil layers.
Use only with Histosols or histic epipedons.
Use only for layers found below the soil surface.
In NASIS, use permanently frozen water to convey permafrost.
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USDA - NRCS
ROCK and OTHER FRAGMENTS
These are discrete, water-stable particles > 2 mm. Hard Rock Fragments
have a Rupture Resistance - Cementation Class Strongly Cemented.
Other Fragments (e.g., soft rock, wood) are less strongly cemented.
Describe Kind, Volume Percent (classes given below), Roundness or
Shape, and Size (mm).
ROCK AND OTHER FRAGMENTS - KIND - Use the choice list given for
Bedrock - Kind and the additional choices in the table below. NOTE:
Interbedded rocks from the “Bedrock - Kind Table” are not appropriate
choices or terminology for rock fragments.
Kind
Code
Kind
Code
NASIS
PDP NASIS
Includes all choices in Bedrock - Kind (except Interbedded), plus:
Calcrete (caliche) 1
--CA Scoria
--SC
Charcoal
--CH Volcanic bombs
--VB
Cinders
E5
CI
Wood
--WO
Lapilli
--LA
PDP
1
Fragments strongly cemented by carbonate, may include fragments
derived from petrocalcic horizons.
ROCK AND OTHER FRAGMENTS - VOLUME PERCENT - Estimate the
quantity on a volume percent basis. NOTE: For proper use of Texture
Modifiers, refer to the “Percent Volume Table” found under Texture.
ROCK AND OTHER FRAGMENTS - ROUNDNESS - Estimate the relative
roundness of rock fragments; use the following classes. (Called Fragment
Roundness in PDP.)
Roundness
Class
Very Angular
Angular
Subangular
Subrounded
Rounded
Well Rounded
1
PDP
--1
2
3
4
5
Code
NASIS
VA
AN
SA
SR
RO
WR
Criteria: visual estimate 1
[ Use Roundness
graphic on next page ]
The criteria consist of a visual estimation; use the following graphic.
USDA - NRCS
2-35
5/13/98
Estimate the relative rounding of rock fragments. (Ideally, use the average
roundness based on 50 or more fragments.) The conventional geologic and
engineering approach is presented in the following graphic. (NOTE: NRCS
does not quantify Sphericity. It is included here for completeness and to
show the range in Fragment Roundness.)
Roundness
Angular
1.5
Sub
Angular
2.5
1, 2
Sub
Rounded
3.5
Rounded
4.5
Well
Rounded
5.5
Sub
Discoidal
1.5
Sub
Prismoidal Prismoidal Spherical
4.5
3.5
2.5
Sphericity
Discoidal
0.5
Very
Angular
0.5
1
2
After Powers, 1953.
Numerical values below roundness and sphericity columns are class
midpoints (median rho values) (Folk, 1955) used in statistical analysis.
5/13/98
2-36
USDA - NRCS
ROCK AND OTHER FRAGMENTS - SIZE CLASSES AND DESCRIPTIVE
TERMS Size 1
Noun
Adjective 2
SHAPE - SPHERICAL or CUBELIKE (discoidal, subdiscoidal, or spherical)
> 2 - 75 mm diameter
gravel
gravelly
> 2 - 5 mm diameter
fine gravel
fine gravelly
> 5 - 20 mm diameter
medium gravel
medium gravelly
> 20 - 75 mm diameter
coarse gravel
coarse gravelly
> 75 - 250 mm diameter
cobbles
cobbly
> 250 - 600 mm diameter
stones
stony
> 600 mm diameter
boulders
bouldery
SHAPE - FLAT (prismoidal or subprismoidal)
> 2 - 150 mm long
channers
channery
> 150 - 380 mm long
flagstones
flaggy
> 380 - 600 mm long
stones
stony
> 600 mm long
boulders
bouldery
1
2
Fragment size is measured by sieves; class limits have a > lower limit.
For a mixture of sizes (e.g., gravels and stones present), the smaller
size must exceed 2X the quantity of the larger size (e.g., 30% gravel
and 14% stones = gravelly; but 20% gravel and 14% stones = stony).
USDA - NRCS
2-37
5/13/98
(SOIL) STRUCTURE
(Soil) Structure is the naturally occurring arrangement of soil particles into
aggregates that results from pedogenic processes. Record Grade, Size,
and Type. For compound structure, list each Size and Type; e.g., medium
and coarse SBK parting to fine GR. Up to ten entries (per horizon) are
permitted in PDP. (For PDP only, estimate the percent of each type.) Lack
of structure (structureless) has two end members: massive (MA) or single
grain (SG). A complete example is: weak, fine, subangular blocky or 1, f,
sbk.
(SOIL) STRUCTURE - TYPE (formerly Shape) Type
Code
Criteria:
Conv NASIS
(definition)
NATURAL SOIL STRUCTURAL UNITS (pedogenic structure)
Granular
gr
GR Small polyhedrals, with curved or very
irregular faces.
Angular
abk ABK Polyhedrals with faces that intersect at
Blocky
sharp angles (planes).
Subangular sbk SBK Polyhedrals with sub-rounded and planar
Blocky
faces, lack sharp angles.
Platy
pl
PL Flat and tabular-like units.
Wedge
--- WEG Elliptical, interlocking lenses that terminate
in acute angles, bounded by slickensides;
not limited to vertic materials.
Prismatic
pr
PR Vertically elongated units with flat tops.
Columnar
cpr COL Vertically elongated units with rounded tops
which commonly are “bleached”.
STRUCTURELESS
Single Grain sg SGR No structural units; entirely noncoherent;
e.g., loose sand.
Massive
m
MA No structural units; material is a coherent
mass (not necessarily cemented).
ARTIFICIAL EARTHY FRAGMENTS OR CLODS 1 (non-pedogenic
structure)
Cloddy 1
--- CDY Irregular blocks created by artificial
disturbance; e.g., tillage or compaction.
1
Used only to describe oversized, “artificial” earthy units that are not
pedogenically derived soil structural units; e.g., the direct result of
mechanical alteration; use Blocky Structure Size criteria.
5/13/98
2-38
USDA - NRCS
Examples of Soil Structure Types
Granular
Blocky
(Subangular)
(Angular)
Prismatic
Columnar
Platy
Wedge
Example of Wedge Structure, Gilgai Microfeatures, & Microrelief
3m
MICRO-HIGH
MICRO-LOW
2m
CaCO3
half-wedge
(merging
slickensides)
Master Slickenside
BOWL
Parallelepiped
Wedge-shaped Ped
Modified from: Lynn and Williams, Soil Survey Horizons, 1992.
USDA - NRCS
2-39
5/13/98
(SOIL) STRUCTURE - GRADE Grade
Structureless
Code
0
Weak
1
Moderate
2
Strong
3
Criteria
No discrete units observable in place or in
hand sample.
Units are barely observable in place or in a
hand sample.
Units well-formed and evident in place or in a
hand sample.
Units are distinct in place (undisturbed soil),
and separate cleanly when disturbed.
(SOIL) STRUCTURE - SIZE Size
Class
Very Fine
(Very Thin 2)
Fine
(Thin 1)
Medium
Coarse
(Thick 2)
Very Coarse
(Very Thick)
Extr. Coarse
1
2
3
Code
Conv NASIS
vf
(vn 1)
f
(tn 1)
m
co
(tk 2)
vc
(vk 2)
ec
VF
(VN 1)
F
(TN 1)
M
CO
(TK 2)
VC
(VK 2)
EC
Criteria:
structural unit size 1 (mm)
Granular
Columnar,
Angular &
Platy 2
Prismatic,
Subangular
Thickness
Wedge 3
Blocky
<1
< 10
<5
1 to < 2
10 to < 20
5 to < 10
2 to < 5
5 to < 10
20 to < 50
50 to < 100
10 to < 20
20 to < 50
10
100 to < 500
50
---
500
---
Size limits always denote the smallest dimension of the structural
units.
For platy structure only, substitute thin for fine and thick for coarse in
the size class names.
Wedge structure is generally associated with Vertisols (for which it is
a requirement) or related soils with high amounts of smectitic clays.
5/13/98
2-40
USDA - NRCS
USDA - NRCS
2-41
5/13/98
5/13/98
2-42
USDA - NRCS
USDA - NRCS
2-43
5/13/98
5/13/98
2-44
USDA - NRCS
USDA - NRCS
2-45
5/13/98
CONSISTENCE
Consistence is the degree and kind of cohesion and adhesion that soil
exhibits, and/or the resistance of soil to deformation or rupture under an
applied stress. Soil-water state strongly influences consistence. Field
evaluations of consistence include: Rupture Resistance (Blocks, Peds, and
Clods; or Surface Crusts and Plates), Resistance to Penetration,
Plasticity, Stickiness, and Manner of Failure. Historically, consistence
applied to dry, moist, or wet soil as observed in the field. Wet consistence
evaluated Stickiness and Plasticity. Rupture Resistance now applies to dry
soils and to soils in a water state from moist through wet. Stickiness and
Plasticity of soil are independent evaluations.
RUPTURE RESISTANCE - A measure of the strength of soil to withstand an
applied stress. Separate estimates of Rupture Resistance are made for
Blocks/Peds/Clods and for Surface Crusts and Plates of soil. Blockshaped specimens should be approximately 2.8 cm across. If 2.8 cm cubes
(e.g., 2.5 - 3.1 cm) are not obtainable, use the following equation and the
table below to calculate the stress at failure: [(2.8 cm / cube length cm)2 X
estimated stress (N) at failure)]; e.g., for a 5.6 cm cube [(2.8/5.6)2 X 20 N = 5
N Soft Class. Plate-shaped specimens (surface crusts or platy structure)
should be approximately 1.0 - 1.5 cm long by 0.5 cm thick (or the thickness
of occurrence, if < 0.5 cm thick).
Blocks/Peds
~ 3 cm
Crusts/Plates
~ 1.0-1.5 cm
5/13/98
2-46
USDA - NRCS
RUPTURE RESISTANCE for:
Blocks, Peds, and Clods - Estimate the class by the force required to
rupture (break) a soil unit. Select the column for the appropriate soil
moisture condition (dry vs. moist) and / or the Cementation column, if
applicable.
Moist
Cementation 1
Code 2 Class Code 2 Class
Code 2
L
Loose L
Not Applicable
d(lo)
m(lo)
Soft
S
Very
VFR NonNC
Friable
Cemented
d(so)
m(vfr)
Slightly
SH
Friable FR
Extremely EW
Hard
Weakly
d(sh)
m(fr) Cemented
Mod.
MH
Firm
FI
Very
VW
Hard
Weakly
d(h)
m(fi) Cemented
Hard
HA
Very
VFI
Weakly
W
Firm
Cemented
d(h)
m(vfi)
c(w)
Very Hard VH
Extr.
EF
Moderately M
Firm
Cemented
d(vh)
m(efi)
Extremely EH
Slightly SR
Strongly
ST
Hard
Rigid
Cemented
d(eh)
m(efi)
c(s)
Rigid
R
Rigid
R
Very
VS
Strongly
d(eh)
m(efi) Cemented
Very
VR
Very
VR
Indurated I
Rigid
Rigid
d(eh)
m(efi)
c(I)
Dry
Class
Loose
1
2
Specimen
Fails Under
Intact specimen
not obtainable
Very slight force
between fingers.
<8 N
Slight force
between fingers.
8 to < 20 N
Moderate force
between fingers.
20 to < 40 N
Strong force
between fingers.
40 to < 80 N
Moderate force
between hands.
80 to < 160 N
Foot pressure by
full body weight.
160 to < 800 N
Blow of < 3 J but
not body weight.
800 N to < 3 J
Blow of 3 J.
(3 J = 2 kg weight
dropped 15 cm).
This is not a field test; specimen must be air dried overnight and
then submerged in water for a minimum of 1 hour prior to test.
Codes in parentheses are obsolete criteria (Soil Survey Staff,
1951).
USDA - NRCS
2-47
5/13/98
Soil Moisture Status (Consistence) (OBSOLETE) - Historical classes
(Soil Survey Staff, 1953).
(d)1 Dry Soil
Class 2
Code
Loose
(d) lo
Soft
(d) so
Slightly Hard (d) sh
Hard 2
(d) h
Very Hard
(d) vh
Extr. Hard
(d) eh
1
2
(m)1 Moist Soil
Cementation
Class
Code
Class
Code
Loose
(m) lo Weakly Cemented (c) w
Very Friable (m) vfr
Friable
(m) fr Strongly Cemented (c) s
Firm
(m) fi
Very Firm
(m) vfi Indurated
(c) I
Extr. Firm
(m) efi
Historically, consistence prefixes (d for dry, m for moist) were
commonly omitted, leaving only the root code; e.g., vfr for mvfr.
Hard Class (Dry) was split into Moderately Hard and Hard (Soil
Survey Staff, 1993).
Surface Crust and Plates Class
(air dried)
Extremely Weak
Very Weak
Weak
Moderate
Moderately Strong
Strong
Very Strong
Extremely Strong
1
Code
EW
VW
W
M
MS
S
VS
ES
Force 1
(Newtons)
Not Obtainable
Removable, < 1N
1 to < 3N
3 to < 8N
8 to < 20N
20 to < 40N
40 to < 80N
80N
For operational criteria [field estimates of force (N)] use the Fails
Under column, in the “Rupture Resistance for Blocks, Peds, Clods
Table”.
CEMENTING AGENTS - Record kind of cementing agent, if present.
Kind
carbonates
gypsum
humus
iron
silica (SiO2)
1
Code 1
K
G
H
I
S
Conventional codes traditionally consist of the entire material name or
its chemical symbols; e.g., silica or SiO2. Consequently, the Conv.
code column would be redundant and is not shown in this table.
5/13/98
2-48
USDA - NRCS
MANNER OF FAILURE - The rate of change and the physical condition soil
attains when subjected to compression. Samples are moist or wetter.
Failure Class
PDP
Code
NASIS
BRITTLENESS
Brittle
Semi-Deformable
B
SD
BR
SD
Deformable
D
DF
Nonfluid
NF
NF
Slightly Fluid
SF
SF
Moderately Fluid
MF
MF
Very Fluid
VF
VF
Non-Smeary 1
NS
NS
Weakly Smeary 1
WS
WS
Moderately
Smeary 1
MS
MS
Strongly
Smeary 1
SM
SM
FLUIDITY
SMEARINESS
1
Criteria:
Related Field Operation
Use a 3 cm block.
(Press between thumb & forefinger.)
Ruptures abruptly (“pops” or shatters).
Rupture occurs before compression to
< 1/2 original thickness.
Rupture occurs after compression to
1/2 original thickness.
Use a palmful of soil.
(Squeeze in hand.)
No soil flows through fingers with full
compression.
Some soil flows through fingers, most
remains in the palm, after full pressure.
Most soil flows through fingers, some
remains in palm, after full pressure.
Most soil flows through fingers, very
little remains in palm, after gentle
pressure.
Use a 3 cm block.
(Press between thumb & forefinger.)
At failure, the sample does not change
abruptly to fluid, fingers do not skid, no
smearing occurs.
At failure, the sample changes abruptly
to fluid, fingers skid, soil smears, little
or no water remains on fingers.
At failure, the sample changes abruptly
to fluid, fingers skid, soil smears, some
water remains on fingers.
At failure, the sample abruptly changes
to fluid, fingers skid, soil smears and is
slippery, water easily seen on fingers.
Smeary failure classes are used dominantly with Andic materials, but
may also be used with some spodic materials.
USDA - NRCS
2-49
5/13/98
STICKINESS - The capacity of soil to adhere to other objects. Stickiness is
estimated at the moisture content that displays the greatest adherence when
pressed between thumb and forefinger.
Stickiness
Class
Non-Sticky
Code
Conv
(w) so
PDP
Slightly Sticky (w) ss
SS
Moderately
Sticky 1
(w) s
S
Very Sticky
(w) vs
VS
1
SO
Criteria: Work moistened soil
NASIS
between thumb and forefinger
SO Little or no soil adheres to fingers, after
release of pressure.
SS Soil adheres to both fingers, after
release of pressure. Soil stretches little
on separation of fingers.
MS Soil adheres to both fingers, after
release of pressure. Soil stretches
some on separation of fingers.
VS Soil adheres firmly to both fingers, after
pressure release. Soil stretches greatly
upon separation of fingers.
Historically, the moderately sticky class was simply called sticky.
PLASTICITY - The degree to which “puddled” or reworked soil can be
permanently deformed without rupturing. The evaluation is made by forming
a roll (wire) of soil at a water content where the maximum plasticity is
expressed.
Plasticity
Class
Non-Plastic
Slightly
Plastic
Moderately
Plastic 1
Very Plastic
1
Code
Conv
(w) po
PDP
(w) ps
SP
(w) p
P
(w) vp
VP
PO
Criteria:
NASIS
Make a roll of soil 4 cm long
PO Will not form a 6 mm diameter roll, or if
formed, can’t support itself if held on end.
SP 6 mm diameter roll supports itself; 4 mm
diameter roll does not.
MP 4 mm diameter roll supports itself, 2 mm
diameter roll does not.
VP 2 mm diameter roll supports its weight.
Historically, the moderately plastic class was simply called plastic.
5/13/98
2-50
USDA - NRCS
PENETRATION RESISTANCE - The ability of soil in a confined (field) state
to resist penetration by a rigid object of specified size. A pocket
penetrometer (Soil-Test Model CL-700) with a rod diameter of 6.4 mm (area
20.10 mm2) and insertion distance of 6.4 mm (note line on rod) is used for
the determination. An average of five or more measurements should be
used to obtain a value for penetration resistance. In PDP, record the
Penetration Resistance value in mega-pascals (MPa), Orientation of the
rod (vertical (V) or horizontal (H)), and Water State of the soil.
NOTE: The pocket penetrometer has a scale of 0.25 to 4.5 tons/ft2 (tons/ft2
kg/cm2). The penetrometer does not directly measure penetration
resistance. The penetrometer scale is correlated to, and gives a field
estimate of unconfined compressive strength of soil as measured with a TriAxial Shear device. The table below converts the scale reading on the
pocket penetrometer to penetration resistance in MPa. Penetrometer
readings are dependent on the spring type used. Springs of varying strength
are needed to span the range of penetration resistance found in soil.
Penetrometer
Scale Reading
tons / ft2
0.25
0.75
1.00
1.50
2.75
3.50
1
2
3
Spring Type 1, 2, 3
Original
MPa
0.32 L
0.60
0.74
1.02 M
1.72
2.14 H
Lee
MPa
0.06 VL
0.13 L
0.17
0.24
0.42
0.53
Jones 11
MPa
1.00 M
1.76
2.14 H
2.90
4.80
---
Jones 323
MPa
3.15 H
4.20
4.73
5.78
8.40 EH
---
On wet or “soft” soils, a larger “foot” may be used (Soil Survey Staff,
1993).
Each bolded value highlights the force associated with a rounded value
on the penetrometer scale that is closest to a Penetration Resistance
Class boundary. The bolded letter; e.g., M, represents the moderate
Penetration Resistance Class from the following table.
Each spring type spans only a part of the range of penetration
resistance possible in soils; various springs are needed to span all
Penetration Resistance Classes.
USDA - NRCS
2-51
5/13/98
Penetration Resistance
Class
Extremely Low
Very Low
Low
Moderate
High
Very High
Extremely High
Code
EL
VL
L
M
H
VH
EH
Criteria:
Penetration Resistance (MPa)
< 0.01
0.01 to < 0.1
0.1 to < 1
1 to < 2
2 to < 4
4 to < 8
8
EXCAVATION DIFFICULTY - The relative force or energy required to dig
soil out of place. Describe the Excavation Difficulty Class and the moisture
condition (moist or dry, but not wet); use the “(Soil) Water State Table”; e.g.,
moderate, moist or M, M. Estimates can be made for either the most limiting
layer or for each horizon.
Class
Low
Moderate
High
Very High
Extremely
High
5/13/98
Code
Criteria
L
Excavation by tile spade requires arm pressure
only; impact energy or foot pressure is not needed.
M
Excavation by tile spade requires impact energy or
foot pressure; arm pressure is insufficient.
H
Excavation by tile spade is difficult, but easily done
by pick using over-the-head swing.
VH Excavation by pick with over-the-head swing is
moderately to markedly difficult. Backhoe
excavation by a 50-80 hp tractor can be made in a
moderate time.
EH Excavation via pick is nearly impossible. Backhoe
excavation by a 50-80 hp tractor cannot be made
in a reasonable time.
2-52
USDA - NRCS
ROOTS
Record the Quantity, Size, and Location of roots in each horizon. NOTE:
Describe Pores using the same Quantity and Size classes and criteria as
Roots (use the combined tables). A complete example for roots is: Many,
fine, roots In Mat at Top of Horizon or 3, f (roots), M.
ROOTS - QUANTITY (Roots and Pores) - Describe the quantity (number) of
roots for each size class in a horizontal plane. (NOTE: Typically, this is
done across a vertical plane, such as a pit face.) Record the average
quantity from 3 to 5 representative unit areas. CAUTION: The unit area that
is evaluated varies with the Size Class of the roots being considered. Use
the appropriate unit area stated in the Soil Area Observed column of the
“Size (Roots and Pores) Table”. In NASIS and PDP, record the actual
number of roots/unit area (which outputs the appropriate class). Use class
names in narrative description.
Quantity Class 1
Few
Very Few 1
Moderately Few 1
Common
Many
1
2
Code
Conv NASIS
1
#
--#
--#
2
#
3
#
Average Count 2
(per unit area)
< 1 per area
< 0.2 per area
0.2 to < 1 per area
1 to < 5 per area
5 per area
The Very Few and Moderately Few sub-classes can be described for
roots (optional) but do not apply to pores.
The applicable area for appraisal varies with the size of roots or pores.
Use the appropriate area stated in the Soil Area Assessed column of
the “Size (Roots and Pores) Table” or use the following graphic.
ROOTS - SIZE (Roots and Pores) - See the following graphic for size.
Size Class
Very Fine
Fine
Medium
Coarse
Very Coarse
1
Conv
vf
f
m
co
vc
Code
NASIS
VF
F
M
C
VC
Diameter
< 1 mm
1 to < 2 mm
2 to < 5 mm
5 to < 10 mm
10 mm
Soil Area 1
Assessed
1 cm2
1 cm2
1 dm2
1 dm2
1 m2
One dm2 = a square that is 10 cm on a side, or 100 cm2.
USDA - NRCS
2-53
5/13/98
ROOTS - QUANTITY (Roots and Pores) - Soil area to be assessed.
5/13/98
2-54
USDA - NRCS
Root and Pore Size Classes
ROOTS - LOCATION (Roots) Location
Between Peds
In Cracks
Throughout
In Mat at Top of Horizon 1
Matted Around Rock Fragments
1
Code
P
C
T
M
R
Describing a root mat at the top of a horizon rather than at the bottom
or within the horizon, flags the horizon that restricts root growth.
USDA - NRCS
2-55
5/13/98
PORES DISCUSSION
Pores are the air or water filled voids in soil. Historically, description of soil
pores, called “nonmatrix” pores in the Soil Survey Manual (Soil Survey Staff,
1993), excluded inter-structural voids, cracks, and in some schemes,
interstitial pores. Inter-structural voids (i.e., the sub-planar fractures between
peds; also called interpedal or structural faces/planes), which can be inferred
from soil structure descriptions, are not recorded directly. Cracks can be
assessed independently (Soil Survey Staff, 1993). Interstitial pores
(i.e. visible, primary packing voids) may be visually estimated, especially for
fragmental soils, or can be inferred from soil porosity, bulk density, and
particle size distribution. Clearly, one cannot assess the smallest interstitial
pores (e.g., < 0.05 mm) in the field. Field observations are limited to those
that can be seen through a 10X hands lens, or larger. Field estimates of
interstitial pores are considered to be somewhat tenuous, but useful.
PORES
Record Quantity and Size of pores for each horizon. Description of soil pore
Shape and Vertical Continuity is optional. A complete example for pores
is: common, medium, tubular pores, throughout or c, m, TU (pores), T.
PORES - QUANTITY - See and use Quantity (Roots and Pores).
PORES - SIZE - See and use Size (Roots and Pores).
PORES - SHAPE (or Type) - Record the dominant form (also called “type”) of
pores discernible with a 10X hand lens and by the unaided eye. (See
following graphic.)
Description
Code
NASIS
Criteria
PDP
SOIL PORES 1
Dendritic
TE
Tubular
Irregular
---
DT
IG
Tubular
TU
TU
Vesicular
VS
VE
Cylindrical, elongated, branching voids; e.g.,
empty root channels.
Non-connected cavities, chambers; e.g., vughs;
various shapes.
Cylindrical and elongated voids; e.g., worm
tunnels.
Ovoid to spherical voids; e.g., solidified
pseudomorphs of entrapped, gas bubbles
concentrated below a crust; most common in
arid to semi-arid environments.
PRIMARY PACKING VOIDS 2
IR
IR
Interstitial
Voids between sand grains or rock fragments.
5/13/98
2-56
USDA - NRCS
1
2
Called “Nonmatrix Pores” in the Soil Survey Manual (Soil Survey Staff,
1993).
Primary Packing Voids include a continuum of sizes. As used here,
they have a minimum size that is defined as pores that are visible with
a 10X hand lens. Primary Packing Voids are called “Matrix Pores” in
the Soil Survey Manual (Soil Survey Staff, 1993).
Tubular
Vesicular
(e.g. small worm tunnels)
(e.g. isolated, spherical-ovoid cavities)
Dendritic Tubular
Irregular
(e.g. abandoned root channels)
(e.g. vughs)
Interstitial
(e.g. primary packing voids)
Rock Fragments
Sand
Fine Earth
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PORES - VERTICAL CONTINUITY - The average vertical distance through
which the minimum pore diameter exceeds 0.5 mm. Soil must be moist or
wetter.
Class
Low
Moderate
High
Conv.
-------
Code
NASIS
L
M
H
Criteria:
vertical distance
< 1 cm
1 to < 10 cm
10 cm
CRACKS
Also called “Extra-Structural Cracks” (Soil Survey Staff, 1993) are fissures
other than those attributed to soil structure. Cracks are commonly vertical,
sub-planar, polygonal, and are the result of desiccation, dewatering, or
consolidation of earthy material. Cracks are much longer and can be much
wider than planes that surround soil structural units such as prisms, columns,
etc. Cracks are key to preferential flow, also called “bypass flow” (Bouma, et
al., 1982) and are a primary cause of temporal (transient) changes in
ponded infiltration and hydraulic conductivity in soils (Soil Survey Staff,
1993). Cracks are primarily associated with, but not restricted to, clayey
soils and are most pronounced in high shrink-swell soils (high COLE value).
Record the Kind, Depth, and Relative Frequency (Areal Percentage). A
complete example is: 3, 25 cm deep, reversible trans-horizon cracks.
Trans-horizon
cracks
Crust-related
cracks
Ap
crust
B
soil structure
(sub-planar,
inter-ped
voids)
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CRACKS - KIND - Identify the dominant types of fissures.
Kind
Code 1
General Description
CRUST-RELATED CRACKS 2 (shallow, vertical cracks related to crusts;
derived from raindrop-splash and soil puddling, followed by dewatering /
consolidation and desiccation)
Reversible CrustRCR Very shallow (e.g., 0.1 - 0.5 cm); very transient
Related Cracks 3
(generally persist less than a few weeks);
formed by drying from surface down; minimal,
seasonal influence on ponded infiltration (e.g.,
rain-drop crust cracks).
ICR Shallow (e.g., 0.5 - 2 cm); seasonally transient
Irreversible CrustRelated Cracks 4
(not present year-round nor every year); minor
influence on ponded infiltration (e.g., freezethaw crust & associated cracks).
TRANS-HORIZON CRACKS 5 (deep, vertical cracks that commonly extend
across more than one horizon and may extend to the surface; derived
from wetting and drying or original dewatering and consolidation of parent
material)
Reversible TransRTH Transient (commonly seasonal; close when
Horizon Cracks 6
rewetted); large influence on ponded infiltration
and Ksat; formed by wetting and drying of soil;
(e.g. Vertisols, vertic subgroups).
ITH Permanent (persist year-round; see Soil
Irreversible TransHorizon Cracks 7
Taxonomy), large influence on ponded
infiltration and Ksat (e.g., extremely coarse
subsurface fissures within glacial till; drained
polder cracks).
1
2
3
4
5
6
7
No conventional codes, use entire term; NASIS codes are shown.
Called “Surface-Initiated Cracks” (Soil Survey Staff, 1993).
Called “Surface-Initiated Reversible Cracks” (Soil Survey Staff, 1993).
Called “Surface-Initiated Irreversible Cracks” (Soil Survey Staff, 1993).
Also called “Subsurface-Initiated Cracks” (Soil Survey Staff, 1993).
Called “Subsurface-Initiated Reversible Cracks” (Soil Survey Staff,
1993).
Called “Subsurface-Initiated Irreversible Cracks” (Soil Survey Staff,
1993).
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Crust-related Cracks
Trans-horizon Cracks
Reversible
Reversible
Irreversible
Irreversible
0.1 - 0.5 cm
0.5 - 2 cm
sand
soil
structure
soil
structure
CRACKS - DEPTH - Record the Average, Apparent Depth (also called a
“depth index value” in the Soil Survey Manual), measured from the surface,
as determined by the wire-insertion method (
2 mm diameter wire). NOTE:
This method commonly gives a standard but conservative measure of the
actual fracture depth. Do not record this data element for cracks that are not
open to the surface. Depth (and apparent vertical length) of subsurface
cracks can be inferred from the Horizon Depth column of layers exhibiting
subsurface cracks.
CRACKS - RELATIVE FREQUENCY - Record the Average Number of
Cracks, per meter, across the surface or Lateral Frequency across a soil
profile as determined with a line-intercept method. This data element cannot
be assessed from cores or push tube samples.
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SPECIAL FEATURES
Record Kind and Area (%) Occupied. Describe the special soil feature by
kind, and estimate the cross sectional area (%) of the horizon that the feature
occupies. In PDP, three items are grouped in this data element: 1) Special
Features - both Kind (e.g., krotovinas and tongues) and the Percent (%) of
Area Covered (the area a feature occupies within a horizon); 2) Percent of
Profile - estimate the area of the profile an individual horizon comprises; and
3) Percent (Volume) of Pedon occupied.
SPECIAL FEATURES - KIND - Identify the kind of special soil feature.
Kind
desert
pavement
1
2
Code 1
DP
hydrophobic
layer
HL
ice wedge cast
IC
krotovinas
lamellae 2
KR
---
lamina
LN
microbiotic
crust
MC
stone line
SL
Tongues of
Albic Material
Tongues of
Argillic Material
E
Criteria
A natural, concentration of closely packed and
polished stones at the soil surface in a desert (may
or may not be an erosional lag).
Either a surface or subsurface layer that repels
water (e.g. dry organic materials; scorch layers in
chaparral, etc.).
A vertical, often trans-horizon, wedge-shaped or
irregular form caused by infilling of a cavity as an
ice wedge melts, commonly stratified.
Filled faunal burrows.
Thin (e.g., > 1 cm), pedogenically formed plates
or intermittent layers.
Thin (e.g., < 1 cm), geogenically deposited strata
or layers of alternating texture (e.g., silt and fine
sand or silt and clay).
Thin, biotically dominated ground or surface crusts;
e.g., cryptogamic crust (algae, lichen, mosses, or
cyanobacteria).
A natural concentration of rock fragments caused
by water erosoion or transport erosional lag (i.e.
carpedolith).
B
Conventional codes consist of the entire name; e.g., Tongues of Albic
Material. Consequently, no Conv. code is shown.
In NASIS, described under Diagnostic Horizon or Property - Kind.
SPECIAL FEATURES - AREA (%) OCCUPIED - Estimate the cross
sectional area (%) of the horizon that the feature occupies.
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PERMEABILITY / SATURATED HYDRAULIC
CONDUCTIVITY (DISCUSSION)
The traditional SCS (now NRCS) concept of soil permeability and
permeability classes are becoming obsolete. The concept of permeability
was originally derived from the “permeability coefficient” as used by
engineers (Soil Survey Staff, 1951). Specifically, the permeability coefficient
represents the ability of a porous medium to transmit fluids or gases. It is a
unitless coefficient totally independent of the working fluid; e.g., water, air,
hydrocarbons, molasses.
Permeability (as traditionally used by NRCS) considers only water, at field
saturation, as the working fluid. This results in units of length / time; (e.g.,
inches / hour, cm / hr, etc.) and values that can’t be extrapolated to other
fluids (e.g., hydrocarbons). Furthermore, permeability (as used by NRCS)
has changed through time. The original work (O’Neil, 1952) measured falling
head, vertical Ksat for a limited number of soil cores and referred to the
permeability coefficient. Over time, the term “coefficient” was dropped.
Extrapolation and inference from the original, modest Ksat data set resulted in
widespread estimations of the ability of other soils to internally transmit
water. Hence, permeability is now a qualitative estimate who’s “values” (i.e.,
classes) are inferred from soil texture or other proxies instead of actual
measurements (Exhibit 618-9, NSSH; Soil Survey Staff, 1996c). It is a soil
quality, as is soil tilth, which cannot be directly quantified.
A much preferred parameter (and concept) has largely replaced permeability.
Hydraulic Conductivity (K) is the current standard for measuring a soil’s
ability to transmit water. Hydraulic conductivity quantifies a material’s ability
to transmit water. Hydraulic conductivity is a numerical variable in an
equation that can be either measured or estimated. It is one of the terms in
Darcy’s law: Q = K A i, [where “Q” is outflow (volume), “K” is the hydraulic
conductivity of the material, “A” is the area through which the fluid moves per
unit time, and “i” is the pressure gradient (Head / Length); (Amoozegar
and Warrick, 1986; Bouma, et al., 1982)].
Hydraulic conductivity under saturated conditions is called Saturated
Hydraulic Conductivity (Ksat) and is the easiest condition to assess. It is
also the most common reference datum used to compare water movement in
different soils, layers, or materials.
Permeability is a qualitative estimate of the relative ease with which soil
transmits water. Hydraulic conductivity is a specific mathematical coefficient
(quantitative) that relates the rate of water movement to the hydraulic
gradient.
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Direct measurement of saturated hydraulic conductivity (Ksat) is strongly
recommended rather than an estimation of permeability inferred from other
soil properties. NOTE: It’s highly recommended to determine the Ksat of a
soil layer by averaging at least three determinations ( replications); more
reps (e.g., 5) are preferred. Ksat is notoriously variable due to unequal
distribution of soil pores and temporal changes in some soil voids (e.g.,
cracks, bio-pores, etc.). Replications help to capture the natural variation of
Ksat within soils and to reduce the influence of data population outliers.
NOTE: As with the virtuous child and the non-virtuous look-alike, superficial
similarities are deceptive. Permeability and Ksat are not synonyms and
should not be treated as such.
PERMEABILITY
Estimate the Permeability Class for each horizon. Guidelines for estimating
permeability are found in Exhibit 618-9, NSSH (Soil Survey Staff, 1996c).
Permeability
Class
Impermeable
Very Slow
Slow
Moderately Slow
Moderate
Moderately Rapid
Rapid
Very Rapid
1
PDP
IM
VS
S
MS
M
MR
RA
VR
Code
NASIS
IM
VS
SL
MS
MO
MR
RA
VR
Criteria:
estimated in / hr 1
< 0.0015
0.0015 to < 0.06
0.06 to < 0.2
0.2 to < 0.6
0.6 to < 2.0
2.0 to < 6.0
6.0 to < 20
20
These class breaks were originally defined in English units and are
retained here, as no convenient metric equivalents are available.
SATURATED HYDRAULIC CONDUCTIVITY (KSAT)
Saturated Hydraulic Conductivity is used to convey the rate of water
movement through soil under (field) saturated conditions. Record the
Average Ksat (X), Standard Deviation (s), and Number of Replications (n)
of each major layer/horizon as measured with a constant-head method (e.g.,
Amoozemeter, Guelph Permeameter, etc.). NOTE: This data element
should be measured rather than estimated and subsequently placed into
classes. Estimates of water movement based on texture or other proxies
must use the preceding “Permeability Class Table”.
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Ksat
Class
Very Low
Low
Mod. Low
Mod. High
High
Very High
1
2
Code 1
PDP
NASIS
1
2
3
4
5
6
#
#
#
#
#
#
Criteria 2:
cm / hr
in / hr
< 0.0036
< 0.001417
0.00360 to < 0.036
0.001417 to < 0.01417
0.0360 to < 0.360
0.01417 to < 0.1417
0.360 to < 3.60
0.1417 to < 1.417
3.60 to < 36.0
1.417 to < 14.17
36.0
14.17
There are no “codes” for Ksat; record the average of measured Ksat
values (#) which can then be assigned to the appropriate class.
For alternative units commonly used for these class boundaries [e.g.,
Standard International Units (Kg s / m3)], see the Soil Survey Manual
(Soil Survey Staff, 1993; p 107).
CHEMICAL RESPONSE
Chemical response is the response of a soil sample to an applied chemical
solution or a measured chemical value. Responses are used to identify the
presence or absence of certain materials; to obtain a rough assessment of
the amount present; to measure the intensity of a chemical parameter (e.g.,
pH.); or to gauge the “reducing” status of the soil.
REACTION (pH) - (Called Field pH in NASIS.) Record the pH value to the
nearest tenth, as measured by pH meter for 1:1 (water:soil), or estimated by
the Hellige-Truog field kit. In PDP, record pH by other techniques (e.g.,
CaCl2 or Lamotte pH) as a User Defined Property.
Descriptive Term
Ultra Acid
Extremely Acid
Very Strongly Acid
Strongly Acid
Moderately Acid
Slightly Acid
Neutral
Slightly Alkaline
Moderately Alkaline
Strongly Alkaline
Very Strongly Alkaline
1
Code 1
#
#
#
#
#
#
#
#
#
#
#
Criteria: pH range
< 3.5
3.5 to 4.4
4.5 to 5.0
5.1 to 5.5
5.6 to 6.0
6.1 to 6.5
6.6 to 7.3
7.4 to 7.8
7.9 to 8.4
8.5 to 9.0
> 9.0
No “codes”; enter the measured value; class is assigned by PDP.
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EFFERVESCENCE - The gaseous response (seen as bubbles) of soil to
applied HCl (carbonate test), H2O2 (MnO2 test), or other chemicals.
Commonly, 1 N HCL is used. Apply the chemical to the soil matrix (for
HCL, effervescence refers only to the matrix; do not include carbonate
masses, which are described as “concentrations”). Record Effervescence
Class and Chemical Agent. A complete example is: strongly effervescent
with 1N-HCL or 2, I. In PDP, record percent of carbonate (measured with a
carbonate field kit) as a User Defined Property.
Effervescence - Class Effervescence Class
Code
NASIS
NE
VS
SL
ST
VE
Criteria
PDP
Noneffervescent
Very Slightly Effervescent
Slightly Effervescent
Strongly Effervescent
Violently Effervescent
4
0
1
2
3
No bubbles form.
Few bubbles form.
Numerous bubbles form.
Bubbles form a low foam.
Bubbles form a thick foam.
Effervescence - Location - Use locations (and codes) from (Ped &
Void) Surface Features - Location. NOTE: Application of chemicals
(e.g., HCL acid) to soil matrix makes many location choices invalid.
Effervescence - Chemical Agent Effervescence Agent
HCl (unspecified) 1
Code
NASIS
H
H1
HCl (1N) 1, 2
I
H2
HCl (3N) 1, 3
J
H3
HCl (6N) 1, 4
---
H4
H2O2 (unspecified) 5, 6
P
P1
H2O2 5, 6
O
P2
Criteria
PDP
1
2
Hydrochloric Acid:
Concentration Unknown
Hydrochloric Acid:
Concentration = 1 Normal
Hydrochloric Acid:
Concentration = 3 Normal
Hydrochloric Acid:
Concentration = 6 Normal
Hydrogen Peroxide:
Concentration Unknown
Hydrogen Peroxide:
Concentration 3-4%
Positive reaction indicates presence of carbonates (e.g., CaCO3).
Concentration of acid preferred for the effervescence field test.
NOTE: A (1N HCl) solution is made by combining 1 part
concentrated (37%) HCl (which is widely available) with 11 parts
distilled H2O.
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3
4
5
6
This concentration is not used for determining Effervescence
Class, but is required for the calcium carbonate equivalent test
(CO2 evolution, not effervescence). An approximately 3N HCl
solution (actually 10% HCl or 2.87N) is made by combining 6
parts concentrated (37%) HCl (which is widely available) with 19
parts distilled H2O.
This concentration is not used for determining Effervescence
Class, but is preferred for the dolomite test (effervescence by
dolomitic carbonates). A 6N HCl solution is made by combining 2
parts concentrated (37%) HCl (which is widely available) with 11
parts distilled H2O. Soil sample should be saturated in a spot
plate and allowed to react for 1-2 minutes; froth = positive
response. Reaction is slower and less robust than CaCO3
effervescence.
Positive reaction indicates presence of manganese oxides (e.g.,
MnO2).
Some forms of organic matter will react slowly with (3-4%) H2O2,
whereas Mn reacts rapidly.
REDUCED CONDITIONS Chemical
Agent
, ‘-dipyridyl 1
1
Code
Criteria
P (= positive)
N (= negative)
, ‘-dipyridyl conc.= 0.2%,
(Childs, 1981)
Positive reaction indicates presence of Fe+2 (i.e., reduced conditions).
SALINITY - The concentration of dissolved salts (more soluble than gypsum;
e.g., NaCl) in a water extract. Estimate the Salinity Class. If the electrical
conductivity is measured, record the actual value and the method used.
Salinity Class
Non-Saline
Very Slightly Saline
Slightly Saline
Moderately Saline
Strongly Saline
Code
0
1
2
3
4
Criteria:
(Electrical Conductivity)
dS/m (mmhos/cm)
<2
2 to < 4
4 to < 8
8 to < 16
16
SODIUM ADSORPTION RATIO (SAR) - An indirect estimate of the
equilibrium between soluble sodium (Na) in a salt solution and the
exchangeable Na adsorbed by the soil (Soil Survey Staff, 1995). It is
presented in the form of a ratio. It is used for soil solution extracts and
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irrigation waters to express the relative activity of sodium (Na) ions in
exchange reactions with the soil. It is calculated from: SAR = [Na+] / [([Ca+2]
+ [Mg+2]) / 2] 0.5, where “x” is the cation concentration in millimoles per liter.
As a field method, it is commonly determined with soil paste and an
electronic wand.
ODOR
Record the presence of any strong smell, by horizon. No entry implies no
odor. (Proposed for addition to NASIS.)
Odor - Kind
Sulphurous
Code
S
Petrochemical
P
Criteria
Presence of H2S (hydrogen sulfide);
“rotten eggs”; commonly associated with
strongly reduced soil containing sulfur
compounds.
Presence of gaseous or liquid gasoline,
oil, creosote, etc.
MISCELLANEOUS FIELD NOTES
Use additional adjectives, descriptors, and sketches to capture and convey
pertinent information and any features for which there is no pre-existing data
element or code. Record such additional information as free-hand notes
under Field Notes (“User Defined Entries” in PDP).
MINIMUM DATA SET (for a soil description)
Purpose, field logistics, habits, and soil materials all influence the specific
properties necessary to “adequately” describe a given soil. However, some
soil properties or features are so universally essential for interpretations or
behavior prediction that they should always be recorded. These include:
Location, Horizon, Horizon Depth, Horizon Boundary, Color,
Redoximorphic Features, Texture, Structure, and Consistence.
PROFILE DESCRIPTION FORM
[ To be developed. ]
PROFILE DESCRIPTION EXAMPLE
[ To be developed. ]
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PROFILE DESCRIPTION REPORT EXAMPLE (for Soil
Survey Reports)
[ To be developed. ]
REFERENCES
Amoozegar, A. and A.W. Warrick. 1986. Hydraulic conductivity of saturated
soils: field methods. In: Klute, A. (ed). 1986. Methods of soil
analysis: Part 1, Physical and mineralogical methods, 2nd ed.
American Society of Agronomy, Agronomy Monograph No. 9, Madison,
WI.
ASSHTO. 1986a. Recommended practice for the classification of soils and
soil-aggregate mixtures for highway construction purposes. ASSHTO
Designation: M145-82. In: Standard specifications for transportation
materials and methods of sampling and testing; Part 1 - Specifications
(14th ed.). American Association of State Highway and Transportation
Officials, Washington, D.C.
ASSHTO. 1986b. Standard definitions of terms relating to subgrade, soilaggregate, and fill materials. ASSHTO Designation: M146-70 (1980).
In: Standard specifications for transportation materials and methods of
sampling and testing; Part 1 - Specifications (14th ed.). American
Association of State Highway and Transportation Officials, Washington,
D.C.
ASTM. 1993. Standard classification of soils for engineering purposes
(Unified Soil Classification System). ASTM designation: D2487-92. In:
Soil and rock; dimension stone; geosynthetics. Annual book of ASTM
standards - Vol. 04.08.
Bates, R.L., and Jackson, J.A. (eds). 1987. Glossary of Geology, 3rd Ed.
American Geological Institute, Alexandria, VA. 788 pp.
Bouma, J., Paetzold, R.F., and Grossman, R.B. 1982. Measuring hydraulic
conductivity for use in soil survey. Soil Survey Investigations Report
No. 38. USDA - Soil Conservation Service, U.S. Gov. Print. Office,
Washington, D.C. 14 pp.
Brewer, R. 1976. Fabric and mineral analysis of soils. Krieger Publishing
Co., Huntington, NY. 482 pp.
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Bullock, P., Fedoroff, N., Jongerius, A., Stoops, G., Tursina, T. 1985.
Handbook for soil thin section description. Waine Research
Publications, Wolverhampton, England. 152 pp.
Childs, C.W. 1981. Field tests for ferrous iron and ferric-organic complexes
(on exchange sites or in water-soluble forms) in soils. Australian
Journal of Soil Research. 19:175-180.
Cruden, D.M., and Varnes, D.J. 1996. Landslide types and processes. In:
Turner, A.K., and Schuster, R.L., eds. Landslides investigation and
mitigation. Special Report 247, Transportation Research Board,
National Research Council, National Academy Press, Washington,
D.C. 675 pp.
Guthrie, R.L. and Witty, J.E. 1982. New designations for soil horizons and
layers and the new Soil Survey Manual. Soil Science Society America
Journal. 46:443-444.
Folk, R.L. 1955. Student operator error in determination of roundness,
sphericity and grain size. Journal of Sedimentary Petrology. 25:297301.
Ingram, R.L. 1982. Modified Wentworth scale. In: Grain-size scales. AGI
Data Sheet 29.1. In: Dutro, J.T., Dietrich, R.V., and Foose, R.M.
1989. AGI data sheets for geology in the field, laboratory, and office,
3rd edition. American Geological Institute, Washington, D.C.
International Soil Science Society. 1993. In: Soil Survey Manual. Soil
Survey Staff, USDA - Soil Conservation Service, Agricultural Handbook
No. 18, U.S. Gov. Print. Office, Washington, D.C. 503 pp.
Lynn, W., and D. Williams. 1992. The making of a Vertisol. Soil Survey
Horizons. 33:23-52.
National Institute of Standards and Technology. 1990. Counties and
equivalent entities of the United States, it’s possessions and associated
areas. U.S. Dept. Commerce, Federal Information Processing
Standards Publication (FIPS PUB 6-4).
Natural Resources Conservation Service. 1996b. The national PLANTS
database. USDA - National Plant Data Center, Baton Rouge, LA.
(electronic database).
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O’Neil, A.M. 1952. A key for evaluating soil permeability by means of
certain field clues. Soil Science Society America Proceedings. 16:312315.
Peterson, F.F. 1981. Landforms of the basin and range province: Defined
for soil survey. Nevada Agricultural Experiment Station Technical
Bulletin 28, University of Nevada - Reno, Reno, NV. 52 pp.
Powers, M.C. 1953. A new roundness scale for sedimentary particles.
Journal of Sedimentary Petrology. 23:117-119.
Public Building Service. Sept. 1996. Worldwide geographic location codes.
U.S. General Services Administration, Washington, D.C.
Ruhe, R.V. 1975. Geomorphology: geomorphic processes and surficial
geology. Houghton-Mifflin Co., Boston, MA. 246 pp.
Schoeneberger, P.J., Wysocki, D.A. 1996. Geomorphic descriptors for
landforms and geomorphic components: effective models, weaknesses
and gaps. [Abstract]. American Society of Agronomy, Annual
Meetings, Indianapolis, IN.
Soil Conservation Service. 1981. Land Resource Regions and Major Land
Resource Areas of the United States. USDA Agricultural Handbook
296. U.S. Gov. Print. Office, Washington, D.C.
Soil Survey Staff. 1951. Soil Survey Manual. USDA - Soil Conservation
Service, Agricultural Handbook No. 18, U.S. Gov. Print. Office,
Washington, D.C. 437 pp.
Soil Survey Staff. 1962. Supplement to Agricultural Handbook No.18, Soil
Survey Manual (replacing pages 173-188). USDA - Soil Conservation
Service, U.S. Gov. Print. Office, Washington, D.C.
Soil Survey Staff. 1983. National Soil Survey Handbook, Part 603, p.45.
USDA - Soil Conservation Service, U.S. Gov. Print. Office, Washington,
D.C.
Soil Survey Staff. 1993. Soil Survey Manual. USDA - Soil Conservation
Service, Agricultural Handbook No. 18, U.S. Gov. Print. Office,
Washington, D.C. 503 pp.
Soil Survey Staff. 1995. Soil survey laboratory information manual. USDA Natural Resources Conservation Service, Soil Survey Investigations
Report No. 45, Version 1.0, National Soil Survey Center, Lincoln, NE.
305 pp.
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Soil Survey Staff. 1996a. Data Dictionary. In: National Soils Information
System (NASIS), Release 3.0. USDA - Natural Resource Conservation
Service, National Soil Survey Center, Lincoln, NE.
Soil Survey Staff. 1996b. Keys to Soil Taxonomy, 7th ed. USDA - Soil
Conservation Service, U.S. Gov. Print. Office, Washington, D.C.
644 pp.
Soil Survey Staff. 1996c. National Soil Survey Handbook. USDA - Natural
Resources Conservation Service, National Soil Survey Center, Lincoln,
NE.
Soil Survey Staff. 1996d. Pedon Description Program, version 4 design
documents. National Soil Survey Center, Lincoln, NE. (unpublished)
Vepraskas, M.J. 1992. Redoximorphic features for identifying aquic
conditions. North Carolina Agricultural Research Service Technical
Bulletin 301, North Carolina State University, Raleigh, NC. 33 pp.
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GEOMORPHIC DESCRIPTION SYSTEM
(Version 2.06 - 9/4/97)
P.J. Schoeneberger, D.A. Wysocki, NRCS, Lincoln, NE
PART I: PHYSIOGRAPHIC LOCATION
A) Physiographic Division
B) Physiographic Province
C) Physiographic Section
D) State Physiographic Area
E) Local Physiographic / Geographic Name
PART II:
A)
B)
C)
D)
GEOMORPHIC DESCRIPTION
Landscape
Landform
Microfeature
Anthropogenic Features
PART III:
A)
B)
C)
D)
E)
F)
G)
SURFACE MORPHOMETRY
Elevation
Slope Aspect
Slope Gradient
Slope Complexity
Slope Shape
Hillslope - Profile Position
Geomorphic Component
1. Hills
2. Terraces
3. Mountains
4. Flat Plains (Proposed)
H) Microrelief
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NOTE: Italicized NASIS short-codes, if available, follow each choice.
PART I: PHYSIOGRAPHIC LOCATION
Reference: A, B, & C see Fenneman’s 1946 map (reprinted 1957), and
Wahrhaftig, 1965.
Physiographic Divisions (A)
Physiographic Provinces (B)
Physiographic Sections (C)
Laurentian Upland
LU
1. Superior Upland
SU
Atlantic Lowland
AL
2. Continental Shelf
CS
3. Coastal Plain
a. Embayed section
b. Sea Island section
c. Floridian section
d. East Gulf Coastal plain
e. Mississippi alluvial valley
f. West Gulf Coastal plain
Appalachian
Highlands
5/13/98
AH
CP
EMS
SIS
FLS
EGC
MAV
WGC
4. Piedmont Province
a. Piedmont upland
b. Piedmont lowlands
PP
PIU
PIL
5. Blue Ridge Province
a. Northern section
b. Southern section
BR
NOS
SOS
6. Valley and Ridge Province
a. Tennessee section
b. Middle section
c. Hudson Valley
VR
TNS
MIS
HUV
7. St. Lawrence Valley
a. Champlain section
b. St. Lawrence Valley,
- northern section
SL
CHS
8. Appalachian Plateau
a. Mohawk section
b. Catskill section
c. Southern New York sect.
d. Allegheny Mountain sect.
e. Kanawaha section
AP
MOS
CAS
SNY
AMS
KAS
3-2
NRS
USDA - NRCS
f. Cumberland Plateau sect.
g. Cumberland Mountain sect.
CPS
CMS
9. New England Province
a. Seaboard lowland sect.
b. New England upland sect.
c. White Mountain section
d. Green Mountain section
e. Taconic section
NE
SLS
NEU
WMS
GMS
TAS
10. Adirondack Province
Interior Plains
IN
AD
11. Interior Low Plateaus
a. Highland rim section
b. Lexington lowland
c. Nashville basin
d. Possible western section
(not delimited on map)
IL
HRS
LEL
NAB
WES
12. Central Lowland Province
a. Eastern lake section
b. Western lake section
c. Wisconsin driftless section
d. Till plains
e. Dissected till plains
f. Osage plain
CL
ELS
WLS
WDS
TIP
DTP
OSP
13. Great Plains Province
a. Missouri plateau, glaciated
b. Missouri plateau, unglaciated
c. Black Hills
d. High Plains
e. Plains Border
f. Colorado Piedmont
g. Raton section
h. Pecos valley
i. Edwards Plateau
k. Central Texas section
GP
MPG
MPU
BLH
HIP
PLB
COP
RAS
PEV
EDP
CTS
This division includes portions of Alaska
(see “Alaskan Physiographic Areas”)
Interior Highlands
USDA - NRCS
IH
14. Ozark Plateau
a. Springfield-Salem plateaus
b. Boston “Mountains”
3-3
OP
SSP
BOM
5/13/98
15. Ouachita Province
a. Arkansas Valley
b. Ouachita Mountains
Rocky Mountain
System
OU
ARV
OUM
16. Southern Rocky Mountains
SR
17. Wyoming Basin
WB
18. Middle Rocky Mountains
MR
19. Northern Rocky Mountains
NR
RM
This division includes portions of Alaska
(see “Alaskan Physiographic Areas”)
Intermontane
Plateaus
IP
20. Columbia Plateau
a. Walla Walla Plateau
b. Blue Mountain section
c. Payette section
d. Snake River Plain
e. Harney section
CR
WWP
BMS
PAS
SRP
HAS
21. Colorado Plateau
a. High Plateaus of Utah
b. Uinta Basin
c. Canyon Lands
d. Navajo section
e. Grand Canyon section
f. Datil section
CO
HPU
UIB
CAL
NAS
GCS
DAS
22. Basin and Range Province
a. Great Basin
b. Sonoran Desert
c. Salton Trough
d. Mexican Highland
e. Sacramento section
BP
GRB
SOD
SAT
MEH
SAS
This division includes portions of Alaska
(see “Alaskan Physiographic Areas”)
Pacific Mountain
5/13/98
PM
23. Cascade-Sierra Mountains
a. Northern Cascade Mtns.
b. Middle Cascade Mtns.
c. Southern Cascade Mtns.
d. Sierra Nevada
3-4
CM
NCM
MCM
SCM
SIN
USDA - NRCS
24. Pacific Border Province
a. Puget Trough
b. Olympic Mountains
c. Oregon Coast Range
d. Klamath Mountains
e. California Trough
f. California Coast Ranges
g. Los Angeles Ranges
PB
PUT
OLM
OCR
KLM
CAT
CCR
LAR
25. Lower California Province
LC
This division includes portions of Alaska
(see “Alaskan Physiographic Areas”)
Alaskan Physiographic Areas (Warhaftig, 1965)
The following Alaskan-Peninsula physiographic areas are extensions of the
previous North American Physiographic Divisions (e.g., Rocky Mountain
System). These extensions are presented separately, rather than
intermingled with the previous Division / Province lists because they:
a) constitute a geographically coherent package (Wahrhaftig, 1965);
b) these extensions were not contained within Fennman’s original work
which dealt only with the conterminous U.S. (Fenneman, 1931; 1938; &
1946); and c) Wahrhaftig’s map-unit numbers are independent of, and
inconsistent with Fenneman’s. Wahrhaftig’s original map unit scheme and
numbers are retained here for simplicity in using his map of the Alaskan
peninsula. CAUTION: Wahrhaftig’s map unit numbers should not be
confused with similar map unit numbers from Fenneman’s map for the
conterminous U.S.
Interior Plains
IN
Rocky Mountains
System
RM
USDA - NRCS
1. Arctic Coastal Plain Province
a. Teshekpuk Hills section
b. White Hills section
2. Arctic Foothills Province
a. Northern Section
b. Southern Section
---AF
---
Arctic Mountains Province
3. Delong Mountains section
4. Noatak Lowlands section
5. Baird Mountains section
6. Central & E. Brooks Range sect.
7. Ambler-Chandalar Ridge &
Lowland sect.
AM
-----
3-5
--
5/13/98
NOTE: The map-unit numbering sequence shown here is from Wahrhaftig
(1965), and is independent of, and not consistent with, that of Fenneman.
Intermontane Plateaus
IP
Northern Plateaus Province
-8. Porcupine Plateau section
-a. Thazzik Mountain
9. Old Crow Plain section
-(noted but not described)
10. Olgivie Mountains section
-11. Tintina Valley (Eagle Trough) sect. -12. Yukon-Tanana Upland section
-a. Western Part
b. Eastern Part
13. Northway - Tanacross Lowland sect. -14. Yukon Flats section
-15. Rampart Trough section
-16. Kokrine - Hodzana Highlands sect. -a. Ray Mountains
b. Kokrine Mountains
Western Alaska Province
-17. Kanuti Flats section
-18. Tozitna - Melozitna Lowland sect. -19. Indian River Upland section
-20. Pah River Section
-a. Lockwood Hills
b. Pah River Flats
c. Zane Hills
d. Purcell Mountains
21. Koyukuk Flats section
-22. Kobuk-Selawik Lowland section
-a. Waring Mountains
23. Selawik Hills section
-24. Buckland River Lowland section
-25. Nulato Hills section
-26. Tanana - Kuskowin Lowland sect. -27. Nowitna Lowland section
-28. Kuskokwim Mountains section
-29. Innoko Lowlands section
-30. Nushagak - Big River Hills section -31. Holitna Lowland section
-32. Nushagak-Bristol Bay Lowlnd sect. -33. Seward Peninsula Province
SEP
a. Bendeleben Mountains
b. Kigluaik Mountains
c. York Mountains
5/13/98
3-6
USDA - NRCS
Bering Shelf Province
34. Yukon- Kuskokwim Coastal
Lowland sect.
a. Norton Bay Lowland
35. Bering Platform section
a. St. Lawrence Island
b. Pribilof Island
c. St. Matthew Island
d. Nunivak Island
36. Ahklun Mountains Province
BES
---
---
NOTE: The map-unit numbering sequence shown here is from Wahrhaftig
(1965), and is independent of, and not consistent with, that of Fenneman.
Pacific Mountian
System
PM
Alaska - Aleutian Province
AAC
37. Aleutian Islands section
-38. Aleutian Range section
-39. Alaska Range (Southern Part) sect. -40. Alaska Range (Central &
Eastern Parts) section
-a. Mentasta - Nutzotin Mtn. segment
41. Northern Foothills of the Alaska
Range section
-Coastal Trough Province
-42. Cook Inlet - Susitna Lowland sect. -43. Broad Pass Depression section
-44. Talkeetna Mountains section
-a. Chulitna Mountains
b. Fog Lakes Upland
c. Central Talkeetna Mountains
d. Clarence Lake Upland
e. Southeastern Talkeetna Mountains
45. Upper Matanuska Valley section
-46. Clearwater Mountains section
-47. Gulkana Upland section
-48. Copper River Lowland section
-a. Eastern Part
b. Western Part: Lake Louis Plateau
49. Wrangell Mountains section
-50. Duke Depression (not described)
51. Chatham Trough section
-52. Kupreanof Lowland section
-Pacific Border Ranges Province
53. Kodiak Mountains section
USDA - NRCS
3-7
PBS
-5/13/98
54. Kenai - Chugach Mountains sect.
55. St Elias Mountains section
a. Fairweather Range subsection
56. Gulf of Alaska Coastal section
57. Chilkat - Baranof Mountains sect.
a. Alsek Ranges subsection
b. Glacier Bay subsection
c. Chichagof Highland subsection
d. Baranof Mountains subsection
58. Prince of Whales Mountains sect.
Coast Mountains Province
59. Boundary Pass section
60. Coastal Foothills section
-----
--
COM
---
Other Physiographic Areas
(not addressed by Fenneman, 1946; or Wahrhaftig, 1965)
Pacific Rim
PR
Pacific Islands Province
a. Hawaiian Islands
b. Guam
c. Trust territories *
d. other (?)
PI
HAI
GUM
TRT
* Most of the former U.S. Trust Territories of the Pacific are now
independent nations. This designation is used here soley for brevity and
to aid in accessing archived, historical data.
Caribbean Basin
CB
Caribbean Islands Province
CI
a. Greater Antilles (Puerto Rico) GRA
b. Lesser Antilles (U.S. Virgin Is.) LEA
c. other (?)
Undesignated
UN
Other
(reserved for temporary, or international designations)
OT
State Physiographic Area (E)
(OPTIONAL)
(Entries presently undefined; to be
developed in conjunction with each State
Geological Survey; target scale is
approximately 1:100,000.)
Local Physiographic / Geographic Name (F)
(OPTIONAL)
5/13/98
(Entries presently undefined; to be
developed in conjunction with each State
3-8
USDA - NRCS
Geological Survey; may include area
names found on USGS 7.5 & 15 minute
topographic maps; target scale is
approximately 1:24,000.)
Sources:
Fenneman, N.M. 1931. Physiography of the western United States.
Mcgraw-Hill Co., New York, NY. 534 p.
Fenneman, N.M. 1938. Physiography of the eastern United States.
Mcgraw-Hill Co., New York, NY. 714 p.
Fenneman, N.M. 1946 (reprinted 1957). Physical divisions of the United
States. U.S. Geological Survey, U.S. Gov. Print. Office,
Washington, D.C. 1 sheet; 1:7,000,000.
Wahrhaftig, C. 1965. Physiographic divisions of Alaska. U.S. Geological
Survey Professional Paper 482. 52p.
USDA - NRCS
3-9
5/13/98
PART II: GEOMORPHIC DESCRIPTION (OUTLINE)
A)
Landscape Terms
B)
Landform Terms
i)
ii)
Alphabetical List (comprehensive, master list)
Landform Subset Lists (landform terms grouped by “process” or
common setting)
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Beach, Coastal, Marine, and Lacustrine Landforms
Depressional Landforms
Eolian Landforms
Erosional Landforms
Fluvial Landforms
Glacial Landforms
Mass Movement Landforms
Periglacial Landforms
Solution Landforms
Slope Landforms
Tectonic, Structural, and Volcanic Landforms
Wetland Terms and Landforms
Water “Landforms” and Related Terms
C)
Microfeature Terms
D)
Anthropgenic Terms
5/13/98
3-10
USDA - NRCS
NOTE: Italicized NASIS short-codes, if available, follow each choice.
PART II: GEOMORPHIC DESCRIPTION
A)
Landscape
(LF = Landform)
badlands
bajada (also LF)
basin
bolson
breaks
canyonlands
coastal plain (also LF)
delta plain (also LF)
drumlin field
dune field
fan piedmont (also LF)
foothills
hills (singular = LF)
intermontane basin (also LF)
island (also LF)
karstland
lava plateau (also LF)
B)
BA
BJ
BS
BO
BK
-CP
---FP
FH
HI
IB
-KP
LL
marine terrace (also LF)
meander belt
mountains (singular = LF)
piedmont
plains (also LF)
plateau (also LF)
river valley
sandhills
sand plain
scabland
semi-bolson
shore complex
tableland
thermokarst
till plain (also LF)
upland
valley (also LF)
-MB
MO
PI
PL
PT
RV
SH
-SC
SB
-TB
TK
TP
UP
VA
Landform
(LS = Landscape; micro = microfeature; w = water body. Italicized
NASIS code follows each term.)
i)
Alphabetical Landform List
a’a lava flow
alas
alluvial fan
alluvial flat
anticline
arete
arroyo
ash flow (also material)
atoll
avalanche chute
backshore
backswamp
bajada (also LS)
ballena
USDA - NRCS
-AA
AF
AP
AN
AR
AY
AS
AT
AL
AZ
BS
BJ
BL
ballon
bar
barchan dune
barrier beach
barrier flat
barrier island
basin floor
basin-floor remnant
bay (w)
bayou (w)
beach
beach plain
beach ridge
beach terrace
3-11
BV
BR
BQ
BB
BP
BI
BC
BD
WB
WC
BE
BP
BG
BT
5/13/98
berm
BM
blind valley
VB
block field (also material)
BW
block glide (also material)
-block stream (also material) BX
blowout
BY
bluff
BN
bog (also wetland)
BO
braided stream
BZ
butte
BU
caldera
CD
canyon
CA
Carolina Bay
CB
channel (also micro)
CC
chenier
CG
chenier plain
CH
cinder cone
CI
cirque
CQ
cliff
CJ
coastal plain (also LS)
CP
col
CL
collapsed ice-floored lakebed CK
collapsed ice-walled lakebed CN
collapsed lake plain
CS
collapsed outwash plain
CT
complex landslide
-coulee
CE
cove
CO
crater (volcanic)
CR
crevasse filling
CF
cuesta
CU
cutoff
CV
debris avalanche
(also material)
DA
debris flow (also material)
DF
debris slide (also material)
-deflation basin
DB
delta
DE
delta plain (also LS)
DC
depression
DP
diapir
DD
dike
DK
dipslope
DL
disintegration moraine
DM
divide
DN
dome
DO
5/13/98
drainageway
draw
drumlin
dune
earth flow (also material)
end moraine
ephemeral stream
(also micro)
erosion remnant
escarpment
esker
estuary (w)
faceted spur
fall (also material)
fan
fan apron
fanhead trench
fan piedmont (also LS)
fan remnant
fan skirt
fault-line scarp
fen
fjord (w)
flat
flood plain
flood-plain playa
flood-plain splay
flood-plain step
flute
fold (also structure)
foredune
fosse
free face
gap
giant ripple
glacial drainage channel
glacial lake (w)
glacial lake (relict)
gorge
graben
ground moraine
gulch
gut (channel); (w)
gut (valley)
hanging valley
headland
3-12
DQ
DW
DR
DU
EF
EM
-ER
ES
EK
WD
FS
FB
FC
FA
FF
FG
FH
FI
FK
FN
FJ
FL
FP
FY
FM
FO
FU
FQ
FD
FV
FW
GA
GC
GD
WE
GL
GO
GR
GM
GT
WH
GV
HV
HE
USDA - NRCS
headwall
HW
highmoor bog
HB
hill
HI
hogback
HO
horn
HR
horst
HT
inselberg
IN
inset fan
IF
interdune
ID
interfluve (also Geom.
Component - Hills)
IV
intermittent stream
(also micro)
-intermontane basin (also LS) IB
island (also LS)
-kame
KA
kame moraine
KM
kame terrace
KT
kettle
KE
kipuka
-knob
KN
knoll
KL
lagoon (w)
WI
lahar (also material)
LA
lake (w)
WJ
lakebed (relict)
LB
lake plain
LP
lakeshore
LF
lake terrace
LT
landslide (also material)
LK
lateral moraine
LM
lateral spread (also material) -lava flow
LC
lava plain
LN
lava plateau (also LS)
LL
lava tube
-ledge
LE
levee (stream)
LV
loess bluff
LO
loess hill
LQ
longshore bar [relict]
LR
louderback (also structure) LU
lowmoor bog
LX
marine terrace
MT
marsh
MA
mawae
-USDA - NRCS
meander
MB
meandering channel
MC
meander scar
MS
meander scroll
MG
medial moraine
MH
mesa
ME
monadnock
MD
monocline (also structure) MJ
moraine
MU
mountain (also LS)
MM
mountain slope
MN
mountain valley
MV
mud flat
MF
mudflow (also material)
MW
muskeg
MX
natural levee
NL
notch
NO
nunatak
NU
outwash fan
OF
outwash plain
OP
outwash terrace
OT
overflow stream (channel)
-oxbow
OX
oxbow lake (w)
WK
oxbow lake (ephemeral)
OL
paha
PA
pahoehoe lava flow
-paleoterrace (or relict terrace) -parabolic dune
PB
parna dune
PD
partial ballena
PF
patterned ground
PG
peak
PK
peat plateau
PJ
pediment
PE
perennial stream (w)
-pingo
PI
pitted outwash plain
PM
pitted outwash terrace
-plain (also LS)
PN
plateau (also LS)
PT
playa
PL
playa lake (w)
WL
plug dome
PP
pluvial lake (w)
WM
pluvial lake (relict)
PQ
3-13
5/13/98
pocosin
PO
point bar
PR
pothole (also micro)
PH
pothole lake (w)
WN
pressure ridge (volc)
PU
proglacial lake (w)
WO
proglacial lake (relict)
-raised beach
RA
raised bog
RB
ravine
RV
recessional moraine
RM
reef
RF
ribbed fen
RG
ridge
RI
rim
RJ
rise
-river (w)
-roche mountonnee
RN
rock fall (also micro)
-rock avalanche (also material) -rock glacier
RO
rotational landslide
(also material)
RP
saddle
SA
salt marsh
SM
salt pond (w)
WQ
sand flow (also material)
RW
sand sheet
RX
scarp
RY
scarp slope
RS
scree slope
-sea cliff
RZ
seif dune
SD
shield volcano
-shoal (w)
WR
shoal (relict)
SE
shore
-shrub-coppice dune (micro) SG
sill
RT
sinkhole
SH
slackwater (w)
WS
slide (also material)
SJ
slough (ephemeral water)
SL
slough (permanent water) WU
slump
SK
slump block
SN
5/13/98
soil fall
spit
spur
stack
steptoe
strand plain
strath terrace
stratovolcano
stream (w)
stream terrace
string bog
structural bench
swale (also micro)
swallow hole
swamp
syncline (also structure)
talus slope
terminal moraine
terrace
thermokarst depression
thermokarst lake (w)
tidal flat
till plain (also LS)
tombolo
topple
tor
translational slide
transverse dune
trough
tunnel valley
U-shaped valley
valley
valley flat
valley floor
valley side
valley train
volcanic cone
volcanic dome
volcano
V-shaped valley
wash
washover fan
wave-built terrace
wave-cut platform
wind gap
yardang (also micro)
3-14
-SP
SQ
SR
ST
SS
SU
SV
-SX
SY
SB
SC
TB
SW
SZ
-TA
TE
TK
WV
TF
TP
TO
-TQ
TS
TD
TR
TV
UV
VA
VF
VL
VS
VT
VC
VD
VO
VV
WA
WF
WT
WP
WG
--
USDA - NRCS
yardang trough (also micro)
ii)
--
Landform Subset Lists (Landform terms grouped by “process” or
common setting)
1.
Beach, Coastal, Marine, and Lacustrine Landforms
atoll
backshore
bar
barrier beach
barrier flat
barrier island
beach
beach plain
beach ridge
beach terrace
berm
bluff
chenier
chenier plain
coastal plain
delta
delta plain (also LS)
flat
foredune
headland
island (also LS)
lagoon
2.
lakebed (relict)
lake plain
lake terrace
longshore bar [relict]
marine terrace (also LS)
mud flat
playa
pluvial lake (relict)
raised beach
reef
salt marsh
sea cliff
shoal (relict)
shore
spit
stack
strand plain
tidal flat
tombolo
washover fan
wave-built terrace
wave-cut platform
LB
LP
LT
LR
MT
MF
PL
PQ
RA
RF
SM
RZ
SE
-SP
SR
SS
TF
TO
WF
WT
WP
gulch
gut (valley)
interdune
intermontane basin
kettle
mountain valley
playa
pothole (also micro)
ravine
saddle
slough (ephemeral)
swale (also micro)
GT
GV
ID
IB
KE
MV
PL
PH
RV
SA
SL
SC
Depressional Landforms
alluvial flat
basin floor
basin floor remnant
canyon
Carolina Bay
col
coulee
cove
depression
drainageway
gap
gorge
USDA - NRCS
AT
AZ
BR
BB
BF
BI
BE
BP
BG
BT
BM
BN
CG
CH
CP
DE
DC
FL
FD
HE
-WI
AP
BC
BD
CA
CB
CL
CE
CO
DP
DQ
GA
GO
3-15
5/13/98
trough
U-shaped valley
valley
3.
TR
UV
VA
BQ
BY
DB
DU
FD
ID
LO
LQ
PA
PB
PD
RX
SD
TD
AR
BL
BV
BD
CL
CU
ER
FW
GA
HO
HR
IN
MS
monadnock
notch
paha
partial ballena
peak
pediment
saddle
scarp slope
strath terrace
structural bench
tor
wind gap
MD
NO
PA
PF
PK
PE
SA
RS
SU
SB
TQ
WG
Fluvial Landforms - Dominantly related to concentrated
water (channel flow), both erosional and depositional
processes, and excluding glaciofluvial landforms.
alluvial fan
alluvial flat
arroyo
backswamp
bajada
bar
basin-floor remnant
block stream
5/13/98
loess hill
paha
parabolic dune
parna dune
sand sheet
seif dune
transverse dune
Erosional Landforms - Water erosion (overland flow) related
and excluding fluvial, glaciofluvial, and eolian erosion.
arete
ballena
ballon
basin floor remnant
col
cuesta
erosion remnant
free face
gap
hogback
horn
inselberg
meander scar
5.
VL
VV
Eolian Landforms
barchan dune
blowout
deflation basin
dune
foredune
interdune
loess bluff
4.
valley floor
V-shaped valley
AF
AP
AY
BS
BJ
BR
BD
BX
braided stream
canyon
channel
coulee
cutoff
delta
delta plain (also LS)
drainageway
3-16
BZ
CA
CC
CE
CV
DE
DC
DQ
USDA - NRCS
draw
fanhead trench
fan skirt
flood plain
flood-plain playa
flood-plain splay
flood-plain step
giant ripple
gorge
gulch
gut (valley)
inset fan
levee (stream)
6.
DW
FF
FI
FP
FY
FM
FO
GC
GO
GT
GV
IF
LV
MS
MG
NL
-OX
OL
PE
PR
RV
SU
SX
WA
WG
Glacial Landforms (including glaciofluvial forms)
arete
cirque
col
collapsed ice-floored
lakebed
collapsed ice-walled
lakebed
collapsed lake plain
collapsed outwash plain
crevasse filling
disintegration moraine
drumlin
end moraine
esker
fjord (w)
flute
fosse
giant ripple
glacial drainage channel
glacial lake (relict)
ground moraine
hanging valley
kame
USDA - NRCS
meander scar
meander scroll
natural levee
overflow stream (channel)
oxbow
oxbow lake (ephemeral)
pediment
point bar
ravine
strath terrace
stream terrace
wash
wind gap
AR
CQ
CL
kame moraine
kame terrace
kettle
lateral moraine
medial moraine
moraine
nunatak
outwash fan
outwash plain
outwash terrace
paha
pitted outwash plain
pitted outwash terrace
pressure ridge (ice)
proglacial lake (relict)
recessional moraine
roche mountonnee
rock glacier
terminal moraine
till plain (also LS)
tunnel valley
U - shaped valley
CK
CN
CS
CT
CF
DM
DR
EM
EK
FJ
FU
FV
GC
GD
GL
GM
HV
KA
3-17
KM
KT
KE
LM
MH
MU
NU
OF
OP
OT
PA
PM
---RM
RN
RO
TA
TP
TV
UV
5/13/98
7.
Mass Movement Landforms (including creep forms)
ash flow
avalanche chute
block glide
complex slide
debris avalanche
debris flow
debris slide
earth flow
fall
lahar
landslide
lateral spread
mudflow
8.
blind valley
sinkhole
rock fall (also micro)
rockfall avalanche
rock glacier
rotational landslide
sand flow
slide
slump
slump block
soil fall
talus
topple
translational slide
--RO
RP
RW
SJ
SK
SN
---TS
Periglacial Landforms (modern, relict, and patterned ground)
alas
block field
muskeg
patterned ground
(see Microfeatures)
9.
AS
AL
---DF
-EF
FB
LA
LK
-MW
AA
BW
MX
PG
peat plateau
pingo
rock glacier
string bog
thermokarst depression
PJ
PI
RO
SY
TK
swallow hole
thermokarst depression
TB
TK
Solution Landforms
VB
SH
10. Slope Landforms - Terms that tend to be generic and that
emphasize their form rather than any particular genesis or
process.
bluff
butte
cliff
cuesta
dome
escarpment
faceted spur
fault-line scarp
free face
gap
5/13/98
BN
BU
CJ
CU
DO
ES
FS
FK
FW
GA
headwall
hill (plural = LS)
hogback
horn
horst
inselberg
interfluve (also Geom.
Component - Hills)
knob
knoll
3-18
HW
HI
HO
HR
HT
IN
IV
KN
KL
USDA - NRCS
lahar
ledge
meander scar
mesa
monadnock
mountain
mountain slope
mountain valley
notch
paha
peak
LA
LE
MS
ME
MD
MM
MN
MV
NO
PA
PK
plain (also LS)
plateau (also LS)
ridge
rim
scarp
spur
structural bench
tor
U - shaped valley
V - shaped valley
wind gap
PN
PT
RI
RJ
RY
SQ
SB
TQ
UV
VV
WG
11. Tectonic, Structural, and Volcanic Landforms
a’a lava flow
anticline
caldera
cinder cone
crater (volcanic)
cuesta
diapir
dike
dipslope
dome
fault-line scarp
graben
hogback
horst
kipuka
lahar
lava flow
-AN
CD
CI
CR
CU
DD
DK
DL
DO
FK
GR
HO
HT
-LA
LC
lava plain
lava plateau (also LS)
lava tube
louderback
mawae
monocline
pahoehoe lava flow
plug dome
pressure ridge (volcanic)
scarp slope
shield volcano
steptoe
stratovolcano
structural bench
syncline (also structure)
volcanic cone
volcanic dome
LN
LL
-LU
-MJ
-PP
PU
RS
-ST
SV
SB
SZ
VC
VD
12. Wetland Terms and Landforms (provisional list:
conventional, geologic definitions; not legalistic or regulatory
usage)
alas
backswamp
bog
Carolina Bay
estuary
fen
highmoor bog
lowmoor bog
USDA - NRCS
AA
BS
BO
CB
WD
FN
HB
LX
marsh
mud flat
muskeg
oxbow lake (ephemeral)
peat plateau
playa (intermittent water)
pocosin
pothole (intermittent water)
3-19
MA
MF
MX
OL
PJ
PL
PO
PH
5/13/98
raised bog
ribbed fen
salt marsh
slough (intermittent water)
RB
RG
SM
SL
string bog
swamp
tidal flat
SY
SW
TF
13. Water “Landforms” and Related Terms - Discrete landform
terms but treated generically as “water” in soil survey.
bay
bayou
ephemeral stream
(also micro)
estuary
fjord
glacial lake
gut (channel)
intermittent stream
(also micro)
lagoon
lake
oxbow lake
perennial stream
(w; also micro)
C)
WB
WC
playa lake
pluvial lake
pond (micro)
pool (micro)
pothole (lake)
proglacial lake
river (w)
salt pond
shoal
slackwater
slough (permanent water)
stream (w)
tank (micro)
thermokarst lake
-WD
FJ
WE
WH
-WI
WJ
WK
WL
WM
--WN
WO
-WQ
WR
WS
WU
--WV
--
Microfeature Terms
bar
channel (also LF)
earth pillar
frost boil
groove
gully
hillock
a)
hoodoo
-mound
M:
patterned ground microfeatures
(see below; used in association
with the landform “patterned
ground” (PG))
Periglacial patterned ground microfeatures:
circle
earth hummocks
high-center polygons
ice wedge polygons
low-center polygons
non-sorted circles
palsa, palsen
(= peat hummocks)
5/13/98
--------
-------
polygons
sorted circles
stripes
turf hummocks
-----
--
3-20
USDA - NRCS
b)
Other patterned ground microfeatures:
bar and channel
gilgai
hummocks
pinnacle
pond (also water list)
pool (also water list)
pothole (also LF)
rib
rill
ripple mark
sand boil
scour (mark)
solifluction lobe
D)
-G
--
mima mounds
pimple mounds
-----------
---
solifluction sheet
solifluction terrace
swale (also LF)
tank (also water list)
terracettes
tree-tip mound
tree-tip pit
yardang (also LF)
yardang trough (also LF)
----T
-----
Anthropogenic Features
artificial collapsed depression
(e.g., arising from subsurface
mining subsidence)
G
artificial levees
A
borrow pit
-burial mound
B
cut (road, railroad)
-ditch
-fill
-gravel pit
-landfill
-levelled land
-midden
H
a)
pond (human-made)
-quarry
-railroad bed
D
rice paddy
E
road bed
I
sand pit
-sanitary landfill
-sewage lagoon
-spoil bank
-surface mine
-tillage / management features F
(see below for common, more
specific types)
Tillage / management features (common types):
conservation terrace
(modern)
-double-bedding mound
(i.e., bedding mound
used for timber; lower
Coastal Plain)
-urban land
USDA - NRCS
drainage ditch
furrow
hillslope terrace
(e.g., archeological
features; China, Peru)
inter-furrow
-----
--
3-21
5/13/98
NOTE: Italicized NASIS short-codes, if available, follow each choice.
PART III: SURFACE MORPHOMETRY
A)
Elevation: The height of a point on the earth’s surface, relative to
mean sea level (msl); indicate units; e.g., 106 m or 348 ft.
B)
Slope Aspect: The compass bearing (in degrees, corrected for
declination) that a slope faces, looking downslope; e.g., 287°.
C)
Slope Gradient: The angle of the ground surface (in percent) through
the site and in the direction that overland water would flow; e.g., 18%.
(Commonly referred to as slope.)
D)
Slope Complexity: Describe the relative uniformity (smooth linear or
curvilinear = simple or S) or irregularity (complex or C) of the ground
surface leading downslope through the point of interest; e.g., simple or
S.
Simple vs. Complex
(S&W, 1996)
E)
Slope Shape: Slope shape is described in two directions: 1) up and
down slope (perpendicular (normal) to the contour); and 2) across slope
(along the horizontal contour). In PDP, this data element is split into
two sequential parts (Slope Across and Slope Up & Down ); e.g.,
Linear, Convex or LV.
5/13/98
3-22
USDA - NRCS
Down Slope
(Vertical)
Concave
Concave
Concave
Convex
Convex
Convex
Linear
Linear
Linear
Across Slope
(Horizontal)
Concave
Convex
Linear
Concave
Convex
Linear
Concave
Convex
Linear
Code
PDP3.5
CC, CC
CC, CV
CC, LL
CV, CC
CV, CV
CV, LL
LL, CC
LL, CV
LL, LL
NASIS
CC
CV
CL
VC
VV
VL
LC
LV
LL
LL
LV
LC
VL
VV
VC
CL
CV
CC
(S&W, 1996)
L = Linear
V = Convex
C = Concave
surface flow
pathway
(F) Hillslope - Profile Position (Hillslope Position in PDP): Twodimensional descriptors of parts of line segments (i.e., slope position)
along a transect that runs up and down the slope; e.g., backslope or
BS. This is best applied to transects or points, not areas.
Position
summit
shoulder
backslope
footslope
toeslope
USDA - NRCS
Code
PDP & NASIS
SU
SH
BS
FS
TS
3-23
5/13/98
Simple Slopes
Complex Slopes
BS
SH FS
BS
SH
FS
SH
Summit
Shoulder
SU
SH
Detailed
Scale
Backslope
BS
Footslope
FS
Toeslope
TS
SH
SU
SU
SH
BS
SH
FS
TS
BS
General
Scale
FS
(S&W, 1996)
Geomorphic Component (Geomorphic Position in PDP): Threedimensional descriptors of parts of landforms or microfeatures that are
best applied to areas. Unique descriptors are available for Hills,
Terraces, Mountains, and Flat Plains; e.g., (for Hills) nose slope or NS.
Code
NASIS
IF
HS
NS
SS
BS
PDP
In
te
rf
Head
slope
lu
ve
IF
HS
NS
SS
---
interfluve
head slope
nose slope
side slope
base slope
m
viu
llu
o
c
se
Ba
e
op
Sl
Nose
slope
Alluvial
fill
higher
order
S
sl ide
op
e
1) Hills
Ba
se
low
Sl
er
op
ord
e
er
str
ea
m
G)
stream
(PJS, 1996; adapted from Ruhe, 1975)
5/13/98
3-24
USDA - NRCS
2) Terraces
Code
RI
TR
riser
tread
Uplands
Terraces
riser
Floodplain
Steps
tread
Annual
Floodplain
100 yr Flood
(scarp)
(S&W, 1996)
3) Mountains
mountaintop
mountainflank
upper third mountainflank
center third mountainflank
lower third mountainflank
mountainbase
Code
MT
MF
UT
CT
LT
MB
mountain top
- bare rock
- residuum
- short-trans.
colluvium
(crest, summit)
(mountain sideslopes)
mountain
flank
(colluvial apron)
- colluvium mantled slopes
- complex slopes
- long slopes
- rock outcrops (free faces)
- structural benches
(floodplain)
mountain
base
Alluvium
Colluvium
(S&W, 1996)
- thick colluvium
4) Flat Plains (proposed)
USDA - NRCS
3-25
Code
5/13/98
H)
Microrelief: Small, relative differences in elevation between adjacent
areas on the earth’s surface; e.g., micro-high or MH; or micro-low or
ML.
NOTE: Microfeature Kind and Pattern have been deleted from PDP;
these phenomena and terms are now captured within the data element
“Microfeature”.
REFERENCES
Ruhe, R.V. 1975. Geomorphology: Geomorphic processes and surficial
geology. Houghton-Mifflin, Boston, MA. 246 p.
Schoeneberger, P.J. and Wysocki, D.A. 1996. Geomorphic descriptors for
landforms and geomorphic components: effective models and
weaknesses. Agronomy abstracts, American Society of Agronomy
Annual Meetings, 1996, Indianapolis, IN.
Soil Survey Staff. 1998. Glossary of landforms and geologic materials.
Part 629, National Soil Survey Handbook, USDA, Natural Resources
Conservation Service, National Soil Survey Center, Lincoln, NE.
5/13/98
3-26
USDA - NRCS
Compiled by: P.J. Schoeneberger, D.A. Wysocki, and E.C. Benham, NRCS,
Lincoln, NE.
INTRODUCTION
The purpose of this section is to expand upon and augment the abbreviated
soil taxonomic contents of the “Soil Profile Description Section”.
HORIZON NOMENCLATURE
MASTER AND TRANSITIONAL HORIZONS Horizon
O
A
AB (or AE)
A/B (or A/E
or A/C)
AC
E
EA (or EB)
E/A
E and Bt
BA (or BE)
USDA - NRCS
Criteria 1
Dominated by organic matter (OM); mineral material is
a small percent by volume (< 5% by weight), excludes
illuvial OM; genrally darker than underlying horizons.
Mineral soil, formed at surface or below O, no remnant
rock structure, and both or either: 1) accumulation of
humified organic matter but dominated by mineral
matter, and not E or B; or 2) cultivation properties.
Excludes recent eolian or alluvial deposits (< 75 cm
thick) that retain stratification.
Dominantly A horizon characteristics but also has
some recognizable characteristics of B (or E) horizon.
Discrete, intermingled bodies of two horizons: A and
B (or E or C) material; majority of layer is A material.
Dominantly A horizon characteristics but also has
some recognizable characteristics of C horizon.
Mineral soil, loss of silica, iron, aluminum, or clay
leaving a net concentration of sand and silt; no
remnant rock structure; typically lighter color (higher
value, chroma) and coarser texture than A.
Dominantly E horizon characteristics, but also has
some recognizable characteristics of A (or B) horizon.
Discrete, intermingled bodies of two horizons: E and
A material; majority of layer is E horizon material.
Presence of thin, heavier textured lamellae (Bt) within
a predominantly E horizon with less clay.
Dominantly B characteristics but also has some
recognizable attributes of A (or E) horizon.
4-1
5/13/98
B/A (or B/E)
B
BC
B/C
CB (or CA)
C/B (or C/A)
C
W
R
1
2
Discrete, intermingled bodies of two horizons, majority
of horizon is B (or E) material.
Mineral soil, formed below O, A, or E; little or no rock
structure; and one or more of the following:
1) illuvial accumulation of silicate clay, Fe, Al,
humus, carbonates, gypsum, or silica (one or
more);
2) removal of carbonates;
3) residual accumulation of sesquioxides;
4) sesquioxide coatings;
5) alterations which form silicate clays or liberates
oxides and forms pedogenic structure;
6) brittleness (includes any illuvial horizon,
cemented or not; and excludes horizons of clay
films coating rock fragments or covering finely
stratified, unconsolidated sediments;
discontinuous carbonate accumulation not
contiguous to overlying horizon; and gleyed
layers lacking additional pedogenic features).
Dominantly B horizon characteristics but also has
some recognizable characteristics of the C horizon.
Discrete, intermingled bodies of two horizons; majority
of horizon is B material.
Dominantly C horizon characteristics but also has
some recognizable characteristics of the B (or A)
horizon.
Discrete, intermingled bodies of two horizons; majority
of horizon is C material.
Mineral soil, excludes hard bedrock; layers little
affected by pedogenesis and lacks properties of O, A,
E, or B horizons. May or may not be related to parent
material of the solum.
A layer of liquid water (W) or permanently frozen ice
(Wf) within the soil (excludes water / ice above soil). 2
Hard bedrock.
Soil Survey Staff, 1996.
NRCS Soil Classification Staff, 1997; personal communication.
5/13/98
4-2
USDA - NRCS
HORIZON SUFFIXES Horizon
Suffixes
a
b
c
d
e
f
ff
g
h
i
j
jj
k
m
n
o
USDA - NRCS
Criteria 1
Highly decomposed organic matter (OM); rubbed fiber
content < 17% (by vol.); see e, i.
Buried genetic horizon (not used with in organic materials
or to separate organic from mineral materials.
Concretions or nodules; significant accumulation of
cemented bodies, enriched with Fe, Al, Mn, Ti [cement not
specified except excludes silica (see q)]; not used for
calcite, dolomite, or soluable salts (see z).
Physical root restriction due to high bulk density (natural or
human-made materials / conditions; e.g., lodgement till,
plow pans etc.
Moderately (intermediately) decomposed organic matter;
rubbed fiber content 17-40% (by vol.); see a, i.
Permafrost (permanently frozen soil or ice); excludes
seasonally frozen ice; continuous subsurface ice.
Dry permafrost [permanently frozen soil; not used for
seasonally frozen; no continuous ice bodies (see f )]. 2
Strong gley (Fe reduced and pedogenically removed);
typically 2 chroma; may have other redoximorphic (RMF)
features; not used for geogenic gray colors.
Illuvial organic matter (OM) accumulation (with B:
accumulation of illuvial, amorphous OM sesquioxide
complexes); coats sand and silt particles or more; use Bhs
if significant accumulation of sesquioxides and moist
chroma value 3.
Slightly decomposed organic matter; rubbed fiber content
> 40% (by vol.); see a, e.
Jarosite accumulation 2; e.g., acid sulfate soils.
Evidence of cryoturbation 2; e.g., irregular or broken
boundaries, sorted rock fragments (patterned ground), or
O.M. in lower boundary between active layer and
permafrost layer.
Pedogenic accumulation of carbonates; e.g. CaCO3.
Strong pedogenic cementation or induration (> 90%
cemented, even if fractured); physically root restrictive;
you can indicate cement type by using letter combinations;
e.g., km - carbonates, qm- silica, kqm - carbonates and
silica; sm - iron, ym - gypsum; zm - salts more soluable
than gypsum.
Pedogenic, exchangeable sodium accumulation.
Residual accumulation of sesquioxides.
4-3
5/13/98
p
q
r
s
ss
t
v
w
x
y
z
1
2
Tillage or other disturbance of surface layer (pasture, plow,
etc.). Designate Op for disturbed organic surface; Ap for
mineral surface even if the layer clearly was originally an
E, B, C, etc.
Accumulation of secondary (pedogenic) silica.
Used with C to indicate weathered or soft bedrock (root
restrictive saprolite or soft bedrock; partially consolidated
sandstaone , siltstone or shale; Excavation Difficulty
classes are low to high).
Illuvial accumulation of amorphous, dispersible,
sesquioxides and organic matter complexes and color
value or chroma 4. Used with B horizon; used with h as
Bhs if color value or chroma is 3.
Slickensides; e.g., oblique shear faces 20 - 60° off
horizontal; due to shrink-swell clay action; wedge-shaped
peds and seasonal surface cracks are also commonly
present.
Illuvial accumulation of silicate clays (clayskins, lamellae,
or clay bridging in some part of the horizon).
Plinthite (high Fe, low OM, reddish contents; firm to very
firm moist consistence; irreversible hardening with
repeated wetting and drying).
Incipient color or pedogenic structure development;
minimal illuvial accumulations (excluded from use with
transition horizons).
Fragipan characteristics (brittleness, firmness, bleached
prisms).
Pedogenic accumulation of gypsum.
Pedogenic accumulation of salts more soluable than
gypsum; e.g., NaCl, etc.
Soil Survey Staff, 1996
NRCS Soil Classification Staff, 1998; personal communication.
5/13/98
4-4
USDA - NRCS
HORIZON NOMENCLATURE CONVERSION CHARTS 1951 1
--Aoo
Ao
--A
A1
A2
A3
AB
A&B
AC
B
B1
B&A
B2
B3
G
Cca
Ccs
--D
Dr
--1
2
3
4
Master Horizons and Combinations
1962 2
1981 3
1997 4
O
O
O
--(see Oi)
(see Oi)
O1
Oi and/or Oe
Oi and/or Oe
O2
Oe and/or Oa
Oe and/or Oa
A
A
A
A1
A
A
A2
E
E
A3
AB or EB
AB or EB
AB
--------A&B
A/B or E/B
A/B or E/B
AC
AC
AC
B
B
B
B1
BA or BE
BA or BE
B&A
B/A or B/E
B/A or B/E
B2
B or Bw
B or Bw
B3
BC or CB
BC or CB
------------------C
C
C
------R
R
R
W
-----
Soil Survey Staff, 1951.
Soil Survey Staff, 1962.
Guthrie and Witty, 1982. Additional changes to lithologic
discontinuities.
NRCS Soil Classification Staff, 1997; personal communication.
USDA - NRCS
4-5
5/13/98
Horizon Suffixes
(also called “Horizon Subscripts”, and “Subordinate
Distinctions”)
1951 1
1962 2
1981 3
1997 4
a
a
----b
b
b
b
ca
ca
(see k)
(see k)
cn
cn
c
c
cs
cs
(see y)
(see y)
e
e
----f
f
f
f
ff
------g
g
g
g
h
h
h
h
ir
ir
(see s)
(see s)
i
i
----j
------jj
------k
k
(see ca)
(see ca)
m
m
m
m
sa
sa
n
n
o
o
----p
p
p
p
q
q
(see si)
(see si)
r
r
r
--s
s
(see ir)
(see ir)
si
si
(see q)
(see q)
ss (1991)
------t
t
t
t
v
v
----w
w
----x
x
x
x
y
y
(see cs)
(see cs)
sa
z
z
1
2
3
4
Soil Survey Staff, 1951.
Soil Survey Staff, 1962
Guthrie and Witty, 1982.
NRCS Soil Classification Staff, 1997; personal communication.
5/13/98
4-6
USDA - NRCS
USDA - NRCS
4-7
5/13/98
5/13/98
4-8
USDA - NRCS
REFERENCES
Guthrie, R.L. and Witty, J.E. 1982. New designations for soil horizons and
layers and the new Soil Survey Manual. Soil Science Society America
Journal, vol. 46. p.443-444.
Soil Survey Staff. 1975. Soil Taxonomy: A basic system of soil
classification for making and interpreting soil surveys. USDA - Soil
Conservation Service, Agricultural Handbook No. 436, U.S. Gov. Print.
Office, Washington, D.C. 754 pp.
Soil Survey Staff. 1962. Identification and nomenclature of soil horizons.
USDA - Soil Conservation Service, Suppliment to to Agricultural
Handbook No. 18, U.S. Gov. Print. Office, Washington, D.C.
Soil Survey Staff. 1951. Soil Survey Manual. USDA - Soil Conservation
Service, Agricultural Handbook No. 18, U.S. Gov. Print. Office,
Washington, D.C. 437 pp.
Soil Survey Staff. 1962. Supplement to Agricultural Handbook No.18, Soil
Survey Manual (replacing pages 173-188). USDA - Soil Conservation
Service, U.S. Gov. Print. Office, Washington, D.C.
Soil Survey Staff. 1993. Soil Survey Manual. USDA - Soil Conservation
Service, Agricultural Handbook No. 18, U.S. Gov. Print. Office,
Washington, D.C. 503 pp.
Soil Survey Staff. 1996. Keys to Soil Taxonomy, 7th ed. USDA - Soil
Conservation Service, U.S. Gov. Print. Office, Washington, D C.
644 pp.
USDA - NRCS
4-9
5/13/98
Compiled by: P.J. Schoeneberger, D.A. Wysocki, and E.C. Benham, NRCS,
Lincoln, NE.
INTRODUCTION
The purpose of this section is to expand and augment the geologic
information found or needed in the “Site Description Section” and “Soil Profile
Description Section”.
BEDROCK - KIND
(This table is repeated here from the “Site Selection Section” for convenience
in using the following rock charts.)
Kind
Code 1
NASIS
IGNEOUS-INTRUSIVE
diabase
-diorite
-gabbro
-I4
granite
granodiorite
-IGNEOUS-EXTRUSIVE
aa (lava)
P8
I7
andesite
I6
basalt
dacite
-latite
-obsidian
-IGNEOUS-PYROCLASTIC
ignimbrite
-pyroclastics (coherent) P0
tuff
P1
tuff, acidic
P2
tuff, basic
P3
USDA - NRCS
Code 1
NASIS
Kind
PDP
PDP
DIA
DIO
GAB
GRA
GRD
monzonite
peridotite
pyroxenite
syenite
syenodiorite
------
MON
PER
PYX
SYE
SYD
AAL
AND
BAS
DAC
LAT
OBS
pahoehoe (lava)
pumice (flow, coherent)
rhyolite
scoria (coherent, mass)
trachyte
P9
E6
-E7
--
PAH
PUM
RHY
SCO
TRA
IGN
PYR
TUF
ATU
BTU
tuff breccia
volcanic breccia
volcanic breccia, acidic
volcanic breccia, basic
P7
P4
P5
P6
TBR
VBR
AVB
BVB
5-1
5/13/98
METAMORPHIC
amphibolite
-AMP
metavolcanics
gneiss
M1
GNE
migmatite
granofels
-GRF
mylonite
granulite
-GRL
phyllite
greenstone
-GRE
schist
hornfels
-HOR
serpentinite
marble
L2
MAR
slate
metaconglomerate
-MCN
soapstone (talc)
metaquartzite
M9
MQT
SEDIMENTARY-CLASTICS
arenite
-ARE
porcellanite
argillite
-ARG
sandstone
arkose
A2
ARK
sandstone, calcareous
breccia, non-volcanic
-NBR
shale
(angular fragments)
claystone
-CST
shale, acid
conglomerate
C0
CON
shale, calcareous
(rounded fragments)
conglomerate, calcar.
C2
CCN
shale, clayey
graywacke
-GRY
siltstone
mudstone
-MUD
siltstone, calcareous
orthoquartzite
-OQT
EVAPORITES, ORGANICS, AND PRECIPITATES
chalk
L1
CHA
limestone, arenaceous
chert
-CHE
limestone, argillaceous
coal
-COA
limestone, cherty
dolostone
L3
DOL
limestone, phosphatic
gypsum
-GYP
travertine
limestone
L0
LST
tufa
INTERBEDDED
limestone-sandst.-shale B1
LSS
sandstone-shale
limestone-sandstone
B2
LSA
sandstone-siltstone
limestone-shale
B3
LSH
shale-siltstone
limestone-siltstone
B4
LSI
1
----M5
M4
M8
--
MVO
MIG
MYL
PHY
SCH
SER
SLA
SPS
-A0
A4
H0
POR
SST
CSS
SHA
-H2
ASH
CSH
H3
T0
T2
YSH
SIS
CSI
L5
L6
L7
L4
---
ALS
RLS
CLS
PLS
TRV
TUA
B5
B6
B7
SSH
SSI
SHS
Definitions for bedrock are found in the “Glossary of Landforms and
Geologic Terms”, NSSH - Part 629 (Soil Survey Staff, 1996c), and in the
“Glossary of Geology” (Bates, et al., 1987).
5/13/98
5-2
USDA - NRCS
ROCK CHARTS
The following rock charts (Igneous, Metamorphic, and Sedimentary &
Volcaniclastic) summarize grain size, composition, or genetic differences
between related rock types. NOTE: 1) Most, but not all, of the rocks in these
tables are found in the NASIS (and PDP) choice lists (some are uncommon
in the pedosphere). These additional rock types are included in these charts
for completeness and to aid in the use of geologic literature. 2) Most, but
not all of the rocks presented in these tables can be definitively identified in
the field; some may require additional laboratory analyses; e.g., grain counts,
thin section analyses, etc.
USDA - NRCS
5-3
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5/13/98
5-4
USDA - NRCS
Quartz
No Quartz
crystalline structure )
( amorphous: no
GLASSY
micro. 1 crypto. 2
( crystals visible only
with magnifation )
APHANITIC
( relatively few visible
crystals within a finegrained matrix )
PORPHYRITIC
( crystals visible and
of nearly equal size )
PHANERITIC
trachyte
quartz
latite
latite
latite
porphyry
monzonite
porphyry
monzonite
pyroclastics are shown on the Sedimentary
and Volcaniclastic Rocks chart.
obsidian (and its varieties: perlite,
pitchstone, pumice, scoria)
rhyolite
trachyte quartz-latite
porphyry
porphyry
rhyolite
porphyry
quartzmonzonite
porphyry
quartz
monzonite
syenite
porphyry
syenite
No Quartz
monzonitepegmatite
Quartz
(---)
Potasium (K) Feldspar &
Plagioclase (Na, Ca) Feldspar
in about equal proportions
≈ mafic)
andesite
andesite
porphyry
diorite
porphyry
diorite
No Quartz
diorite
pegmatite
basalt
porphyry
basalt
diabase
gabbro
gabbro
pegmatite
Calcic (Ca)
Plagioclase
}
lava 3
(mostly
pyroxene)
pyroxenite
(mostly olivine)
peridotite
Pyroxene
and
Olivine
Ultrabasic
( ≈ ultramafic)
2
Microcrystalline - crystals visible with ordinary
magnification (hand lens, simple microscope).
Cryptocrystalline - crystals only visible with SEM
3
Lava - generic name for extrusive flows of
non-clastic, aphanitic rocks (rhyolite, andesite, basalt)
1
dacite
dacite
porphyry
quartzdiorite
porphyry
quartzdiorite
granodiorite
Quartz
Sodic (Na)
Plagioclase
Plagioclase (Na, Ca) Feldspar
> 2/3 of Total
Feldspar Content
(
KEY MINERAL COMPOSITION
Basic
Intermediate
granite
porphyry
granite
( very coarse, unevengranite
syenite
sized crystal grains ) pegmatite pegmatite
PEGMATITIC
CRYSTALLINE
TEXTURE
Potasium (K) Feldspar
> 2/3 of Total
Feldspar Content
Acidic
( ≈ Felsic)
IGNEOUS ROCKS CHART
USDA - NRCS
5-5
5/13/98
Grade
High
Grade
metaconglomerate
metavolcanics
crush breccia
mylonite
Very Low
Grade
slate
Low
phyllite
greenstone
Grade
amphibolite
schist
Grade
Medium
REGIONAL
METAMORPHISM
High
gneiss
granulite
Grade
migmatite
Grade
Extreme
PLUTONIC
METAMROPHISM
FOLIATED STRUCTURE (e.g. banded, etc.)
* Not all rock types listed here can be definitively identified in the field (e.g. may require grain counts)
** Not all rock types shown here are available on Bedrock-Kind choice list. They are included here
for completeness and as aids to using geologic literature.
granofels
hornfels
marble
metaquartzite
serpentinite
soapstone (talc)
Medium
Low
MECHANICAL
METAMORPHISM
CONTACT
METAMORPHISM
Grade
CRUDE ALIGNMENT
NONFOLIATED STRUCTURE
METAMORPHIC ROCKS CHART
5/13/98
5-6
USDA - NRCS
arenite
(non-volcanic,
angular frags)
(mainly quartz)
orthoquartzite
(dark, "dirty" ss)
graywacke
("greensand")
(non-volcanic,
rounded frags)
glauconitic ss conglomerate
(mainly feldspar)
arkose
breccia
(Rudaceous)
> 2.0 mm
Coarse
(organics and
fine sediments)
black shale
siliceous rocks (SiO 2 dominated):
chert (jasper, chalcedony, opal)
diatomite
rock phosphate
iron bearing rocks (Fe-SiO 2 dominated)
OTHER NONCLASTIC ROCKS
phosphatic limestone
(angular frags)
(>50% calcite + dolomite)
(specific gravity >2.0; slightly to moderately vesicular)
scoria
biostromal ls
organic reef
pelagic ls
(chalk)
Reduzates
Organic
bio-clastic types bituminous ls
bog iron ores
coquina
oolitic ls
lithographic ls
coal
(altered types):
dolostone
tufa
travertine
caliche
CARBONAT E ROCKS
Limestones (ls)
(>50% calcite)
chemical types accretionary types
Accretionates
(rounded frags)
(NACl)
halite
2H 2 O)
gypsum
(CaSO 4 (CaSO 4 )
anhydrite
Evaporates Precipitates
Biochemical
NONCLASTIC
volcanic breccia
agglomerate
pumice
(specific gravity <1.0; highly vesicular)
tuff
ignimbrite
VOLCANICLASTICS (includes Pyroclastics)
claystone siltstone
mudstone
shale
argillite
(Arenaceous)
0.05 - 2.0 mm
(Argillaceous)
0.002-0.05 mm
(Argillaceous)
<0.002 mm
Sandstones (ss):
Medium
Fine
Very Fine
Dominant Grain Size
Chemical
SEDIMENTARY AND VOLCANICLASTIC ROCKS
CLASTIC
NORTH AMERICAN GEOLOGIC TIME SCALE 1
Geologic Period
Geologic
Epoch
Sub-Division
Holocene
Late
Pleistocene
QUATERNARY
Pleistocene
Middle
Pleistocene
TERTIARY
CRETACEOUS
Late Wisconsin
Mid Wisconsin
Early Wisconsin
Late Sangamon
Sangamon
Late - Mid
Pleistocene
(Illinoian)
Middle - Mid
Pleistocene
Early - Mid
Pleistocene
Oxygen
Isotope
Stage
Years
(BP)
(1)
(2)
(3, 4)
(5a - 5d)
0 to 10-12 ka*
10-12 to 28 ka
28 to 71 ka
71 to 115 ka
(5e)
(6 - 8)
115 to128 ka
128 to 300 ka
(9 - 15)
300 to 620 ka
(16 - 19)
620 to 770 ka
770 ka to
1.64 Ma**
Early
Pleistocene
Pliocene
Miocene
Oligocene
Eocene
Paleocene
1.64 to 5.2 Ma
5.2 to 23.3 Ma
23.3 to 35.4 Ma
35.4 to 56.5 Ma
56.5 to 65.0 Ma
65.0 to 97.0 Ma
97.0 to 145.6 Ma
Late Cretaceous
Early Cretaceous
JURASSIC
145.6 to 208.8 Ma
TRIASSIC
208.8 to 243.0 Ma
243.0 to 290.0 Ma
PERMIAN
PENNSYLVANIAN
290.0 Ma to 322.8 Ma
MISSISSIPPIAN
322.8 to 362.5 Ma
DEVONIAN
362.5 to 408.5 Ma
SILURIAN
408.5 to 439.0 Ma
ORDIVICIAN
439.0 to 510.0 Ma
CAMBRIAN
510.0 to 570.0 Ma
> 570.0 Ma
PRECAMBRIAN
* ka = x 1,000
** Ma = x 1,000,000 ( = approximately)
1 Modified from Morrison, 1991; Sibrava, et al., 1986; Harland, et al., 1990.
USDA - NRCS
5-7
5/13/98
TILL TERMS
Genetic classification and relationships of till terms commonly used in soil
survey. (Schoeneberger, 1994; adapted from Goldthwaite and Matsch,
1988.)
Location
(Facies of tills
grouped by
position at
deposition)
Proglacial Till
(at the front of, or
in front of)
Supraglacial Till
(on top of, or
within upper part
of)
Subglacial Till
(within the lower
part of, or
beneath)
Till Types
Terrestrial
proglacial flow till
supraglacial flow till 1, 3
supraglacial melt-out till 1
(ablation till - NP) 1
(lowered till - NP) 2
(sublimation till - NP) 2
lodgement till 1
subglacial melt-out till
subglacial flow till
(= “squeeze till” 2, 3)
Waterlaid
waterlaid flow till
--------------
waterlaid melt-out till
waterlaid flow till
iceberg till
( = “ice-rafted”)
(basal till - NP) 1
(deformation till - NP) 2
(gravity flow till - NP) 2
1
2
3
Ablation till and basal till, generic terms that only describe “relative
position” of deposition, have been widely replaced by more specific terms
that convey both relative position and process. Ablation till (any
comparatively permeable debris deposited within or above stagnant ice) is
replaced by supraglacial melt-out till, supraglacial flow till, etc. Basal till
(any dense, non-sorted subglacial till) is replaced by lodgement till,
subglacial melt-out till, subglacial flow till, etc.
Additional (proposed) till terms that have not gained wide acceptance, and
considered to be Not Preferred, should not be used.
Also called gravity flow till (not preferred).
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USDA - NRCS
VOLCANICLASTIC TERMS
Volcaniclastic Deposits (Unconsolidated)
Size
Scale:
0.062 mm 1
64 mm 1
2 mm
< tephra >
(all ejecta)
< ash >
< cinders > < bombs >
(specific gravity
(fluid-shaped
> 1.0 & < 2.0)
coarse fragments)
<>
<>
< lapilli >
< blocks >
fine ash
coarse ash
(specific gravity
(angular-shaped
> 2.0)
coarse fragments)
< scoria 2 >
(slightly to moderately vesicular;
specific gravity > 2.0)
<>
< pumice >
pumiceous
(highly vesicular; specific gravity < 1.0)
ash 3
Associated Lithified (Consolidated) Rock Types
<>
<>
<lapillistone>
fine tuff
coarse tuff
(sp. gr. > 2.0)
< ignimbrite >
< agglomerate >
(consolidated ash flows and
(rounded, volcanic coarse fragments)
nuee ardentes )
< volcanic breccia >
(angular, volcanic coarse fragments)
1
2
3
These size breaks are taken from geologic literature (Fisher, 1989) and
based on the modified Wentworth scale. The 0.062 mm break is very
close to the USDA’s 0.05 mm break between coarse silt and very fine
sand (Soil Survey Staff, 1993). The 64 mm break is close to the USDA’s
76 mm break between coarse gravel and cobbles. (See “Relationships
Among Particle Size Classes and Different Systems” in the “Profile /
Pedon Description Section”, under “Soil Texture”.)
A lower size limit of 2 mm is required in Soil Taxonomy, but is not required
in geologic usage (Fisher, 1989).
The descriptor for pumice particles < 2 mm, as used in Soil Science.
Geologic usage does not recognize any size restrictions for pumice.
USDA - NRCS
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5/13/98
REFERENCES
Bates, R.L., and Jackson, J.A. (eds.). 1987. Glossary of geology, 3rd Ed.
American Geological Institute, Alexandria, VA. 788 p.
Fisher, R.V. 1989. Pyroclastic sediments and rocks. AGI Data Sheet 25.2.
In: Dutro, J.T., Dietrich, R.V., and Foose, R.M. 1989. AGI data sheets
for geology in the field, laboratory, and office, 3rd edition. American
Geological Institute, Washington, D.C.
Goldthwaite, R.P. and Matsch, C.L. (eds.). 1988. Genetic classification of
glacigenic deposits: final report of the commission on genesis and
lithology of glacial quaternary deposits of the International Union for
Quaternary Research (INQUA). A.A. Balkema, Rotterdam. 294 p.
Harland, W.B., R.L. Armstrong, L.E. Craig, A.G. Smith, and D.G. Smith.
1990. A geologic time scale. Press Syndicate of University of
Cambridge, Cambridge, UK. 1 sheet.
Morrison, R.B. (ed.). 1991. Quaternary nonglacial geology: conterminous
United States. Geological Society of America, Decade of North
American Geology, Geology of North America, Vol. K-2. 672 p.
Sibrava, V., D.Q. Bowen, and D.Q. Richmond (eds.). 1986. Quaternary
glaciations in the Northern Hemisphere: final report of the International
Geological Correlation Programme, Project 24. Quaternary Science
Reviews, Vol. 5, Pergamon Press, Oxford. 514 p.
Soil Survey Staff. 1995. Soil survey laboratory information manual. USDA Natural Resources Conservation Service, Soil Survey Investigations
Report No. 45, Version 1.0, National Soil Survey Center, Lincoln, NE.
305 pp.
Soil Survey Staff. 1996 (being revised). Glossary of landforms and geologic
materials. Part 629, National Soil Survey Handbook. USDA - Natural
Resources Conservation Service, National Soil Survey Center,
Lincoln, NE.
Tennissen, A.C. 1974. Nature of earth materials. Prentice-Hall, Inc., NJ.
5/13/98
5-10
USDA - NRCS
Compiled by: P.J. Schoeneberger, W. Lynn, D.A. Wysocki, and E.C. Benham,
NRCS, Lincoln, NE.
PUBLIC LAND SURVEY
The Public Land Survey is the most widely used scheme in the U.S. for land
surveying (legal location). Historically, many soil descriptions have been
located using this system. Some states are not part of the Public Land
Survey System and use the State Plane Coordinate System. The states
include Connecticut, Delaware, Georgia, Kentucky, Maine, Maryland,
Massachusetts, New Hampshire, New Jersey, New York, North Carolina,
Ohio (parts), Pennsylvania, Rhode Island, South Carolina, Tennessee,
Texas, Vermont, Virginia, and West Virginia.
The Public Land Survey System consists of a standard grid composed of
regularly spaced squares which are uniquely numbered in reference to northsouth Principle Meridians and to various, local, east-west Baselines. These
squares are shown on U.S. Geological Survey topographic maps.
TOWNSHIPS AND RANGES - The primary grid network consists of squares
(6 miles on a side) called Townships. Each Township can be uniquely
identified using two coordinates: 1) Township (the north-south coordinate
relative to a local, east-west Baseline); and 2) Range (the east-west
coordinate relative to a local north-south Principle Meridian). (The local
Baselines and Principle Meridians for the coterminous U.S. are shown on pp.
82-83, Thompson, 1987.) Commonly in soil survey, the local Baseline and
the Principle Meridian are not recorded. The name of the appropriate USGS
topographic 7.5-minute or 15-minute quadrangle is recorded instead; e.g.,
Pleasant Dale, NE, 7.5 min. Quad.
The Township numbers run in rows that parallel the local Baseline. Each
Township row is sequentially numbered relative to the row’s distance from,
and whether it’s north (N) or south (S) of the local Baseline; e.g., T2N (for the
second township row north of the local Baseline). The Range numbers run
in rows that parallel the local Principle Meridian. Range rows are
sequentially numbered relative to the row’s distance from, and whether it’s
east (E) or west (W) of the Principle Meridian e.g., R2E (for the second
Range row east of the Principle Meridian in the area). The combined
coordinates identify a unique square in the area; e.g., T1S, R2E (for
Township 1 South and Range 2 East).
USDA - NRCS
6-1
5/13/98
T3N
R1W
R1E
Township 3 North
Range 2 West
R2E
N
R3E
36 sq. mi.
6 miles
R2W
T3N
MERIDIAN
6 miles
T1N
BASE
LINE
Township
Lines
T2N
PRINCIPAL
T2N
T1N
6 5
7 8
Local Point
of Origin
Section
= 1 square mile
T1S
4 3 2 1
9 10 11 12
18 17 16 15 14 13
T1S
19 20 21 22 23 24
30 29 28 27 26 25
31 32 33 34 35 36
Township 2 South,
Range 1 West
T2S
R2W
R1W
Section 34 of
T1S - R2E
R1E
R2E
T2S
R3E
Modified from Mozola, 1989.
SECTIONS - Each Township square is further subdivided into smaller
squares called Sections, which make up the secondary grid in this location
system. Sections are 1 mile on a side (for a total of 36 Sections within each
Township). The Section numbers begin in the northeast corner of a
Township and progress sequentially in east-west rows, wrapping back and
forth to fill in the Township; e.g., Section 34, T1S, R2E (for Section 34 of
Township 1 South, Range 2 East).
CAUTION: Due to the curvature of the earth (trying to fit a flat grid to a nonflat surface), inaccessible areas (e.g., large swamps), or to joins to other
survey schemes (e.g., pre-existing Metes and Bounds), you will occasionally
find irregularities in the grid system. Adjustments to the grid layout result in
non-standard sized, partial sections and/or breaks in the usual numbering
sequence of sections. In some areas, Lots are appended to the northernmost tier of Sections in a Township to enable the adjoining Township to
begin along the Baseline.
5/13/98
6-2
USDA - NRCS
SECTION
CORNER
SECTION
CORNER
SECTION LINE
SW¼
160 ACRES
1/8th LINE
34
5A
5 chn. 20 rd.
40 ACRES
20 chains
1320 feet
1/4 post
N
W
10 chns.
660 ft.
80 ACRES
NE¼
10 A
330 ft. 5 chn.
SE¼
SECTION LINE
1/4 post
center
of section
NORTH and SOUTH 1/4 LINE
EAST and WEST 1/4 LINE
20 A
40 chains
E 1/2, NW 1/4, ....
NW 1/4 of ...
NW¼
E 1/2 of SW 1/4 of ....
N 1/2 of
NW 1/4 of
SW 1/4 of .....
S 1/2 of
NW 1/4 of
SW 1/4 of .....
SW 1/4 of
SW 1/4 of .....
40 chains - 2640 feet - 160 rods
SECTION LINE
(of) Section 34,
T15, R2E
Section 34, T15, R2E
NW 1/4 (of) NW 1/4 .....
20 chains
1/4 post
40 rods
10 chains
E
S
40 chains = 2640 feet = 160 rods
1 mile (5280 ft)
Modified from Mozola, 1989.
SUB-DIVISIONS - The tertiary (lower) levels of this system consist of
subdividing Sections into smaller pieces that are halves or quarters of the
Section. The fraction (1/2, 1/4) that the area of land represents of the
Section is combined with the compass quadrant that the area occupies within
the Section; e.g., SW 1/4, Section 34, T1S, R2E (for the southwest quarter of
Section 34, Township 1 South, Range 2 East). Additional subdivisions, by
quarters or halves, can be continued to describe progressively smaller areas.
The information is presented consecutively, beginning with the smallest
subdivision; e.g., N 1/2, NW 1/4, SW 1/4, NW 1/4, of Section 34, T1S, R2E
(for the north half of the northwest quarter of the southwest quarter of the
northwest quarter of Section 34, Township 1 South, Range 2 East).
NOTE: Point locations (e.g., soil pits) are measured, traditionally in English
units, with reference to a specified section corner or quarter corner (1/4 post);
e.g., 660 feet east and 1320 feet north of southwest corner post, Section 34,
T1S, R2E.
USDA - NRCS
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5/13/98
STATE PLANE COORDINATE SYSTEM
The State Plane Coordinate System is the second most widely used scheme
in the U.S. for land surveying (legal location). Historically, many soil
descriptions have been located using this system. The states that use this
system are: Connecticut, Delaware, Georgia, Kentucky, Maine, Maryland,
Massachusetts, New Hampshire, New Jersey, New York, North Carolina,
Ohio (parts), Pennsylvania, Rhode Island, South Carolina, Tennessee,
Texas, Vermont, Virginia, West Virginia. The other states use the Public
Land Survey System.
The State Plane Coordinate System is based upon two principle lines in the
state; a north-south line and an east-west line. Most USGS topographic
quadrangle maps indicate the state grids by tick marks along the neatlines
(outer-most border) on 7.5-minute topographic maps of states that use State
Plane Coordinates.
Specific coordinates for a point are described by distance (commonly in
meters) and primary compass direction [north (northing) / south (southing)
and east (easting) / west (westing)] relative to the principle lines; e.g.,
10,240 m easting, and 1,234 m northing.
Contact the local State NRCS Office or the Regional MO Office for statespecific details.
UNIVERSAL TRANSVERSE MERCATOR (UTM)
RECTANGULAR COORDINATE SYSTEM
The Universal Transverse Mercator (UTM) Rectangular Coordinate System
is widely available and has been advocated as the universal map coordinate
standard by the USGS (Morrison, 1987). It is a metric-based system whose
primary unit of measure is the meter. The dominant UTM projection circles
the globe and spans a wide range of latitudes [80 S through 84 N (the
extreme polar areas require a different projection)]. The dominant projection
is divided into 60 zones around the world. Zones begin at the International
Date Line Meridian in the Pacific and progress eastward around the world.
Each zone extends from pole to pole and spans 6 degrees of longitude. The
logic of the UTM grid is similar to that of State Plane Coordinates. The UTM
System uses 2 values to arrive at unique coordinates for any point on the
earth’s surface: 1) distance (and direction) away from the Equator called
Northing (or Southing) to identify the hemisphere, and 2) distance away
from the local zone’s Meridian called an Easting.
Around the perimeter of 7.5-minute USGS topographic quadrangle maps are
blue tic marks which intersect the map boundary at 1 km intervals. The
5/13/98
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USDA - NRCS
Northing measures the distance from the Equator northward (in the Southern
Hemisphere the Southing measures the distance from the Equator
southward); e.g., 4, 771,651 meters N. The Easting measures the distance
eastward from the local Meridian (the same Easting designation is used in
the Southern Hemisphere); e.g., 305, 904 meters E. A complete example:
305, 904 meters E; 4, 771,651 meters N; 16, N (for the location of the capitol
dome in Madison, Wisconsin, which is located within zone 16).
If the USGS topographic map has a complete kilometer grid (shown in blue),
measure the distance (cm) from the point of interest to the closest northsouth reference line (to the west of the point of interest). If the map scale is
1:24000, multiply the measured distance (cm) by 240 to calculate the actual
ground distance in meters. If the scale is 1:20000, multiply by 200, etc. Add
this partial distance to that of the chosen km reference line to obtain the
Easting to be recorded.
If no kilometer grid is shown on the topographic map, locate the kilometer tic
points along the east-west perimeters immediately south of the point of
interest. Place a straight edge between the tic marks and draw a line
segment south of the point of interest. Measure the distance (cm) from the
point of interest to the east-west line segment. Multiply this distance by the
appropriate map scale factor as mentioned above. Add this distance to that
of the east-west baseline to obtain the Northing (distance from the Equator).
The Northing must be identified as N for sites north of the Equator and S for
sites south of the Equator.
Alternatively, a variety of clear UTM templates are commercially available
which can be overlain upon the topographic map to facilitate determining
distances and coordinates.
REFERENCES
Mozola. A.J. 1989. U.S. Public Land Survey. In: Dutro, J.T., Dietrich, R.V.,
and Foose, R.M. AGI Data Sheets, 3rd Ed., American Geologic
Institute, United Book Press, Inc.
Thompson, M.M. 1987. Maps for America, 3rd Ed. U.S. Geological Survey,
U.S. Dept. Interior, U.S. Gov. Print. Office, Washington, D.C.
USDA - NRCS
6-5
5/13/98
Compiled by: P.J. Schoeneberger, D.A. Wysocki, E.C. Benham, and H. LaGarry,
NRCS, Lincoln, NE.
EXAMPLES OF PERCENT OF AREA COVERED
The following graphic can be used for various data elements to convey
“Amount” or “Quantity”. NOTE: Within any given box, each quadrant
contains the same total area covered, just different sized objects.
2%
5%
15%
20%
25%
35%
50%
60%
90%
USDA - NRCS
7-1
5/13/98
MEASUREMENT EQUIVALENTS & CONVERSIONS
METRIC TO ENGLISH
Known
Symbol
LENGTH
micron
(=10,000 Angstrom units)
millimeters
mm
centimeters
cm
centimeters
cm
meters
m
meters
m
kilometers
km
AREA
square centimeters
cm²
square meters
m²
square meters
m²
square kilometers
km²
hectares
ha
VOLUME
cubic centimeters
cm³
cubic meters
m³
cubic meters
m³
cubic meters
m³
Multiplier
Symbol
3.9370
x 10-5
0.03937
0.0328
0.03937
3.2808
1.0936
0.6214
inches
in or "
inches
feet
inches
feet
yards
miles(statute)
in or "
ft or '
in or "
ft or '
yd
mi
0.1550
10.7639
1.1960
0.3861
2.471
square inches
square feet
square yards
square miles
acres
in²
ft²
yd²
mi²
ac
0.06102
35.3146
1.3079
0.0008107
cubic inches
cubic feet
cubic yards
acre-feet
(= 43,560 ft3)
cubic miles
quarts (U.S.)
gallons (U.S.)
ounces
in³
ft³
yd³
acre-ft
ounces (avdp.)
pounds (avdp.)
short tons
(2000 lb)
long tons
(2240 lb)
oz
lb
cubic kilometers
km³
0.2399
liters (=1000 cm³)
l
1.0567
liters
l
0.2642
milliliter
ml
0.0338
1 milliliter = 1 cm³ = 1 gm (H20, at 25C)
MASS
grams
g
0.03527
kilograms
kg
2.2046
megagrams
Mg
1.1023
(= metric tons)
megagrams
Mg
0.9842
5/13/98
Product
7-2
mi³
qt
gal
oz
USDA - NRCS
ENGLISH TO METRIC
Known
LENGTH
inches
Symbol
Multiplier
in or "
2.54 x 104
Product
micron
[= 10,000 Angstrom units (A)]
centimeters
cm
centimeters
cm
meters
m
meters
m
kilometers
km
inches
in or "
2.54
feet
ft or '
30.48
feet
ft or '
0.3048
yards
yd
0.9144
miles (statute)
mi
1.6093
AREA
square inches
in²
6.4516
sq. centimeters
square feet
ft²
0.0929
sq. meters
square yards
yd²
0.8361
sq. meters
square miles
mi²
2.5900
sq. kilometers
acres
ac
0.405
hectares
VOLUME
acre-feet
acre-ft
1233.5019
cubic meters
acre-furrow-slice
afs
= 6 in. thick layer that’s 1 acre square
2,000,000 lbs
(assumes b.d. = 1.3 g/cm³)
cubic inches
in³
16.3871
cubic centimeters
cubic feet
ft³
0.02832
cubic meters
cubic yards
yd³
0.7646
cubic meters
cubic miles
mi³
4.1684
cubic kilometers
gallons (U.S. liquid)
gal
3.7854
liters
(= 0.8327 Imperial gal)
quarts (U.S. liquid)
qt
0.9463
liters (= 1000 cm³)
ounces
oz
29.57
milliliters
1 milliliter = 1 cm³ = 1 gm (H20, at 25C)
MASS
ounces (avdp.)
oz
28.3495
grams
ounces (avdp.) (1 troy oz. = 0.083 lb)
pounds (avdp.)
lb
0.4536
kilograms
short tons (2000 lb)
0.9072
megagrams
(= metric tons)
long tons (2240 lb)
1.0160
megagrams
USDA - NRCS
7-3
Symbol
cm²
m²
m²
km²
ha
m³
cm³
m³
m³
km³
l
l
ml
g
kg
Mg
Mg
5/13/98
COMMON CONVERSION FACTORS
Known
acres
acre-feet
acre-furrow-slice
2,000,000 lbs
Angstrom units
Angstrom units
Atmospheres
Atmospheres
BTU (mean)
centimeters
centimeters
centimeters/second
centimeters/second
chain (US)
chain (US)
centimeters
cubic centimeters
cubic centimeters
cubic centimeters
cubic feet
cubic feet
(H20, 60F)
cubic feet
cubic inches
cubic kilometers
cubic meters
cubic meters
cubic meters
Symbol
Multiplier
Product
0.405
hectares
ac
1233.5019
cubic meters
acre-ft
= 6 in. thick layer that’s 1 acre square
afs
(assumes b.d. = 1.3 g/cm³)
1x 10-8
centimeters
A
1x 10-4
microns
A
1.0133 x 106
dynes/cm2
A
760
mm of mercury (Hg)
atm
777.98
foot-pounds
BTU
0.0328
feet
cm
0.03937
inches
cm
1.9685
feet/minute
cm/s
0.0224
miles/hour
cm/s
66
feet
4
rods
0.06102
cubic inches
cm³
2.6417 x 10-4 gallons (U.S.)
cm³
0.999972
milliliters
cm³
0.0338
ounces (US)
cm³
0.02832
cubic meters
ft³
62.37
pounds
ft³
ft³
in³
km³
m³
m³
m³
0.03704
16.3871
0.2399
35.3146
1.3079
0.0008107
cubic miles
cubic yards
degrees (angle)
Faradays
fathoms
feet
feet
feet
feet
foot pounds
gallons (US)
gallons (US)
mi³
yd³
4.1684
0.7646
0.0028
96500
6
30.4801
0.3048
0.0152
0.0606
0.0012854
3.7854
0.8327
5/13/98
ft or '
ft or '
ft or '
ft or '
gal
gal
7-4
cubic yards
cubic centimeters
cubic miles
cubic feet
cubic yards
acre-feet
(= 43,560 ft3)
cubic kilometers
cubic meters
circumfrences
coulombs (abs)
feet
centimeters
meters
chains (US)
rods (US)
BTU (mean)
liters
Imperial gallons
Symbol
ha
m³
cm
ft or '
in or "
ft/min.
mph
ft
in³
gal
ml
oz
m³
lbs
yrd³
cm³
mi³
ft³
yd³
acre-ft
km³
m³
ft
cm
m
BTU
l
USDA - NRCS
gallons (US)
gallons (US)
grams
hectares
horsepower
inches
gal
gal
g
ha
in or "
0.1337
128
0.03527
2.471
2545.08
2.54 x 104
cubic feet
ounces (US)
ounces (avdp.)
acres
BTU (mean)/hour
micron
ft³
oz
oz
ac
[= 10,000 Angstrom units (A)]
inches
kilograms
kilometers
joules
liters
liters
liters (= 1000 cm³)
long tons (2240 lb)
megagrams
(= metric tons)
megagrams
in or "
kg
km
J
l
l
l
Mg
2.5400
2.2046
0.6214
1 x 107
0.2642
33.8143
1.0567
1.0160
1.1023
Mg
0.9842
meters
m
3.2808
meters
m
39.37
micron
1 x 10-4
micron
3.9370
(=10,000 Angstrom units)
x 10-5
miles (statute)
mi
1.6093
miles/hour
mph
44.7041
miles/hour
mph
1.4667
milliliter
ml
0.0338
1 milliliter 1 cm³ = 1 gm (H20, at 25C)
milliliter
ml
1.000028
millimeters
mm
0.03937
ounces
oz
29.5729
1 milliliter 1 cm³ = 1 gm (H20, at 25C)
ounces (avdp.)
oz
28.3495
ounces (avdp.)
1 troy oz. = 0.083 lb
pints (US)
pt
473.179
pints (US)
pounds (avdp.)
USDA - NRCS
pt
lb
0.4732
0.4536
7-5
centimeters
pounds (avdp.)
miles (statute)
ergs
gallons (US)
ounces
quarts (US)
megagrams
short tons
(2000 lb)
long tons
(2240 lb)
feet
inches
centimeters
inches
cm
lb
mi
kilometers
cent./second
feet/second
ounces
km
cm/s
ft/s
oz
cubic centimeters
inches
milliliters
cm³
in or "
ml
grams
g
cubic centimeters
cm³
or cc
l
kg
liters
kilograms
gal
oz
qt
Mg
ft or '
in
cm
in or "
5/13/98
quarts (US liquid)
rods (US)
rods (US)
short tons
(2000 lb)
square centimeters
square feet
square inches
square kilometers
square meters
square meters
square miles
square yards
yards
5/13/98
qt
0.9463
0.25
16.5
0.9072
cm²
ft²
in²
km²
m²
m²
mi²
yd²
yd
0.1550
0.0929
6.4516
0.3861
10.7639
1.1960
2.5900
0.8361
0.9144
7-6
liters
(= 1000 cm³)
chains (US)
feet (US)
megagrams
(= metric tons)
square inches
square meters
sq. centimeters
square miles
square feet
square yards
square kilometers
square meters
meters
l
ft
ft
Mg
in²
m²
cm²
mi²
ft²
yd²
km²
m²
m
USDA - NRCS
Guide to Map Scales and Minimum-Size Delineations 1
Order of
Soil
Survey
Order 1
Order 2
Order 3
Order 4
Order 5
Very
General
1
2
3
Map Scale
Inches
Per Mile
1:500
1:1,000
1:2,000
1:5,000
1:7,920
1:10,000
1:15,840
1:20,000
1:24,000 3
1:30,000
1:31,680
1:60,000
1:62,500
1:63,360
1:80,000
1:100,000
1:125,000
1:250,000
1:500,000
1:750,000
1:1,000,000
1:7,500,000
1:15,000,000
126.7
63.4
31.7
12.7
8.0
6.34
4.00
3.17
2.64
2.11
2.00
1.05
1.01
1.00
0.79
0.63
0.51
0.25
0.127
0.084
0.063
0.0084
0.0042
Minimum Size
Delineation 2
Acres
0.0025
0.100
0.040
0.25
0.62
1.00
2.50
4.00
5.7
9.0
10.0
36
39
40
64
100
156
623
2,500
5,600
10,000
560,000
2,240,000
Hectares
0.001
0.004
0.016
0.10
0.25
0.41
1.0
1.6
2.3
3.6
4.1
14.5
15.8
16.2
25.8
40
63
252
1,000
2,270
4,000
227,000
907,000
Modified from: Peterson, F.F. 1981. Landforms of the Basin and Range
Province. Defined for soil survey. Nevada Agricultural Experiment
Station. Technical Bulletin No. 28. Reno, NV. 52 p.
Traditionally, the minimum size delineation is assumed to be a 1/4 inch
square, or a circle with an area of 1/16 inches2. Cartographically, this is
about the smallest area in which a conventional soil map symbol can be
legibily printed. Smaller areas can, but rarely are, delineated and the
symbol “lined in” from outside the delineation.
Corresponds to USGS 7.5-minute topographic quadrangle maps.
USDA - NRCS
7-7
5/13/98
COMMON SOIL MAP SYMBOLS (TRADITIONAL)
(From the National Soil Survey Handbook, Title 170, Part 601, 1990.) The
following symbols are common on field sheets (original aerial photograph
based soil maps) and in many soil surveys published prior to 1997. Current
guidelines for map compilation symbols are in NSSH, Exhibit 627-5, 1997.
FEATURE
SYMBOL
LANDFORM FEATURES:
BaC
SOIL DELINEATIONS:
MiA
ESCARPMENTS:
Bedrock
(Points down slope)
Other than bedrock
(Points down slope)
SHORT STEEP SLOPE
GULLY
DEPRESSION, closed
SINKHOLE
Prominent Hill or Peak
EXCAVATIONS:
Soil Sample Site
S
Borrow pit
Gravel pit
Mine or quarry
LANDFILL
5/13/98
7-8
USDA - NRCS
SYMBOL
FEATURE
MISC. SURFACE FEATURES:
Blowout
Clay spot
Gravelly spot
Lava flow
Marsh or swamp
Rock outcrop (includes
sandstone and shale)
Saline spot
Sandy spot
Severely eroded spot
Slide or slip (tips point upslope)
Sodic spot
Spoil area
Stony spot
Very stony spot
Wet spot
USDA - NRCS
7-9
5/13/98
SYMBOLS
FEATURE
ROAD EMBLEMS :
Interstate
79
79
345
Federal
410
410
224
52
52
347
State
County, farm or ranch
378
RAILROAD
POWER TRANSMISSION LINE
(normally not shown)
PIPELINE
(normally not shown)
FENCE
(normally not shown)
5/13/98
7-10
USDA - NRCS
SYMBOLS
FEATURE
CULTURAL FEATURES (cont'd)
LEVEES:
Without road
With road
With railroad
Single side slope
(showing actual feature location)
DAMS
W
Medium or Small
Large
USDA - NRCS
7-11
5/13/98
HYDROGRAPHIC FEATURES:
STREAMS:
Perennial, double line
Perennial, single line
Intermittent
Drainage end
SMALL LAKES, PONDS
AND RESERVOIRS:
Perrenial water
Miscellaneous water
FLO
Flood pool line
OD
PO
OL
LINE
Lake or pond
(perennial)
MISCELLANEOUS
WATER FEATURES:
Spring
Well, artesian
Well, irrigation
5/13/98
7-12
USDA - NRCS
MISCELLANEOUS
CULTURAL FEATURES:
Farmstead, house
(omit in urban areas)
Church
School
Other Religion (label)
Mt
Carmel
Located object (label)
Ranger
Station
Tank (label)
Petroleum
Lookout Tower
Oil and/or Natural Gas Wells
Windmill
Lighthouse
USDA - NRCS
7-13
5/13/98
Compiled by: P.J. Schoeneberger and D.A. Wysocki, NRCS, Lincoln, NE.
INTRODUCTION
This section contains a variety of miscellaneous information pertinent to the
sampling of soils in the field.
Additional details of soil sampling for the National Soil Survey Laboratory
(NRCS, Lincoln, NE) are provided in Soil Survey Investigations Report
No. 42 (Soil Survey Staff, 1996).
SOIL SAMPLING
The objective of the task determines the methodology and the location of the
soil material collected for analysis. Sampling for Taxonomic Classification
purposes involves different strategies than sampling for soil fertility,
stratigraphy, hydric conditions, etc. There are several general types of
samples and sampling strategies that are commonplace in soil survey.
SOIL SAMPLE KINDS Reference Samples (also loosely referred to as “grab” samples) - This
is applied to any samples that are collected for very specific, limited
analyses; e.g., only pH. Commonly, reference samples are not
collected for all soil layers in a profile; e.g., only the top 10 cm; only the
most root restrictive layer, etc.
Characterization Samples - These samples include sufficient physical
and chemical soil analyses, from virtually all layers, to fully characterize
a soil profile for Soil Taxonomic and general interpretive purposes. The
specific analyses required vary with the type of material; e.g., a Mollisol
requires some different analyses than does an Andisol. Nonetheless, a
wide compliment of data (i.e., pH, particle size analysis, Cation
Exchange Capacity, ECEC, Base Saturation, Organic Carbon content,
etc.) are determined for all major soil layers.
SAMPLING STRATEGIES - [ To be developed. ]
USDA - NRCS
8-1
5/13/98
FIELD EQUIPMENT CHECKLIST Digging Tools (commonly choose 1 or 2; see graphic)
Bucket Auger
Sharp Shooter
Montana Sharp Shooter (for rocky soils)
Tile Spade (for well-cultivated or loose material)
Spade (standard shovel)
Push Probe (e.g., Backsaver, Oakfield, etc.) - include a
clean-out tool
Pulaski
Soil Description
Knife
Hand Lens (10X or combination lenses)
Acid Bottle (1N - HCl)
Water Bottle
Color Book (e.g., Munsell, EarthColors, etc.)
Picture Tapes (“pit tape” - metric preferred)
Tape Measure (metric or English and metric)
(3) Ultra-Fine Point Permanent Marker Pens
Pocket pH Kit or Electronic “Wand”
Pocket Soil Thermometer
Camera
Sample bags (for grab samples)
Soil Description Sheet (232 or PEDON description form)
Site Description
Field Note Book
GPS Unit
Abney Level
Clinometer
Compass
Altimeter (pocket-sized)
Field References
Field Book for Describing and Sampling Soils
Aerial Photographs
Topographic Maps (1:24,000, 7.5 min; 1:100,000)
Geology Maps
Soil Surveys (county or area)
AGI Field Sheets
Personal Protective Gear
Small First Aid Kit
Leather Gloves
Sunglasses
Insect Repellent
Sunscreen
Hat
Drinking Water
5/13/98
8-2
USDA - NRCS
EXAMPLES OF COMMON FIELD SAMPLING EQUIPMENT - (Use of trade
or company names is for informational purposes only and does not constitute
an endorsement.)
Digging Tools / Shovel Types
(all steel)
pulaski
Primary
Use:
standard
shovel
tile spade
sharp-shooter
Montana
sharp-shooter
most
materials
loose
material
most
materials
rocky soil
Soil Probes
Hydraulic Probes
hinged
door
tile probe
regular (solid steel
push-tube
rod)
Primary
Use:
fine
earth
USDA - NRCS
locating
hard
contact
peat
sampler
Giddings tube
Bull probe
(not effective in high
organic General
Use: rock fragment materials)
soils
8-3
5/13/98
Bucket Auger Types
closed
open
Primary
Use:
regular auger
(open teeth)
closed bucket
(open teeth)
sand auger
(pinched teeth)
clays, loams
loams
wet sand
External Thread Augers
push
tube
Primary
Use:
Dutch auger
("mud")
screw auger
(external threads)
organics,
moist muds
rocky soils
flight auger
hollow stem
auger
rocky soils,
deep holes
undisturbed
sample
REFERENCES
Soil Survey Staff. 1996. Soil survey laboratory methods manual. USDA Natural Resources Conservation Service, Soil Survey Investigations
Report No. 42, Version 3.0, National Soil Survey Center, Lincoln, NE.
693 pp.
5/13/98
8-4
USDA - NRCS
Across Slope • 3-23
Air Temperature • 1-1
Anthric Saturation • 1-12
Anthropogenic Feature • 1-4
Anthropogenic Features • 3-21
Area Covered (%) Example • 7-1
Argillans • 2-24
Aspect • See Slope Aspect
Bedrock • 1-18
Hardness • 1-20
Weathering Class • 1-20
Depth To • 1-20
Bedrock-Fracture Interval Class • 1-19
Biological Concentrations • 2-17, 2-19
Bridging • 2-24
Brittleness • 2-49
Bypass Flow • 2-58
Calcium Carbonate Equivalent Test • 2-66
Carpedolith • 2-61
Cementing Agents • 2-48
Characterization Samples • 8-1
Chemical Response • 2-64
Clay Depletions • 2-13
Clay Films • 2-24
Climate • 1-1
Coats • 2-24
Color Location • 2-8
Color, Mechanical Condition • 2-8
Color, Redoximorphic Condition • 2-8
Common Conversion Factors • 7-4
Common Field Sampling Equipment (Examples) • 8-3
Common Horizons • 2-2
Common Soil Map Symbols (Traditional) • 7-8
USDA - NRCS
9-1
5/13/98
Compositional Texture Modifiers • 2-33
Concentrations • 2-18
Boundary • 2-23
Color • 2-20
Contrast • 2-20
Hardness • 2-23
Kind • 2-18
Location • 2-22
Moisture State • 2-20
Quantity • 2-20
Shape • 2-22
Size • 2-20
Concentrations Discussion • 2-17
Concretions • 2-13, 2-17, 2-19
Consistence • 2-46
Contrast Of Soil Mottles • 2-12
Coprogenous Earth • 1-24, 2-33
County FIPS Code • 1-2, 1-3
Cracks • 2-58
Depth • 2-60
Kind • 2-59
Relative Frequency • 2-60
Crust-Related Cracks • 2-59, 2-60
Cryptogamic Crust • 2-61
Crystals • 2-17, 2-19
Date • 1-1
Datum Name • 1-2
Decision Flowchart For Describing Soil Colors • 2-7
Delineation Size (Transect) • 1-3
Densic (Contact, Material) • 1-24
Depth (To Bedrock) • 1-20
Depth To Water Table • 1-13
Describer(s) Name • 1-1
Desert Pavement • 2-61
Diagnostic Horizons • 1-23, 2-4
Diagnostic Properties • 1-23
Diagnostic Properties - Mineral Soils • 1-24
Diagnostic Properties - Organic Soils • 1-24
Diagnostic Subsurface Horizons • 1-23
Diatomaceous Earth • 1-24, 2-33
Down Slope • 3-23
Drainage • 1-9
5/13/98
9-2
USDA - NRCS
Drainage Class • 1-9
Durinode • 1-24, 2-19
Earth Cover - Kind • 1-14
Effervescence • 2-65
Chemical Agent • 2-65
Electrical Conductivity • 2-66
Elevation • 1-4, 3-22
Endosaturation • 1-12
English To Metric • 7-3
Eolian Deposits • 1-16
Epipedons • 1-23
Episaturation • 1-12
Erosion • 1-20
Degree Class • 1-21
Kind • 1-20
Erosional Lag • 2-61
Evaporites • 1-19
Excavation Difficulty • 2-52
Excavation Difficulty Class • 2-52
Extra-Structural Cracks • 2-58
Faunal Burrows • 2-61
Fecal Pellets • 2-19
Ferriargillans • 2-15, 2-24
Field Equipment Checklist • 8-2
Field Notes • 2-67
Field Sampling • 8-1
Filaments • 2-22
Films • 2-15, 2-24
Finely Disseminated Materials • 2-17
FIPS Code • 1-3
Fissures • 2-58
Flat Plains (Geomorphic Components) • 1-8
Flooding • 1-10
Duration • 1-11
Frequency • 1-10
Months • 1-11
Fluidity • 2-49
Fragment Roundness • See Rock And Other Fragments - Roundness
USDA - NRCS
9-3
5/13/98
Geology • 5-1
References • 5-10
Geomorphic Component • 1-7, 3-24
Geomorphic Description • 1-4, 3-1, 3-11
References • 3-26
Geomorphic Description (Outline) • 3-10
Geomorphic Description System • 3-1
Geomorphic Information • 1-4
Gilgai Microfeatures • 2-39
Glacial Deposits • 1-16
Ground Surface • 2-4
Guide To Map Scales And Minimum-Size Delineations • 7-7
Hard Rock Fragments • 2-32
Hills (Geomorphic Components) • 1-7
Hillslope - Profile Position • 1-6, 3-23
Hillslope Position • See Hillslope - Profile Position
Horizon Boundary • 2-5
Distinctness • 2-5
Topography • 2-6
Horizon Depth • 2-4
Horizon Modifiers (Other) • 2-4
Numerical Prefixes • 2-4
Prime • 2-4
Horizon Nomenclature • 2-2, 4-1
Horizon Nomenclature Conversion Charts • 4-5
Horizon Subscripts • See Horizon Suffixes
Horizon Suffixes • 2-3, 4-3
Horizon Thickness • 2-5
Hortonian Flow • 1-21
Hydraulic Conductivity • 2-62
Hydrophobic Layer • 2-61
Hypocoats • 2-15, 2-23, 2-24
Ice Wedge Cast • 2-61
Igneous Rocks • 1-18
Index (Of) Surface Runoff Classes • 1-22
In-Place Deposits • 1-16
Interbedded Rocks • 1-19
5/13/98
9-4
USDA - NRCS
Internal Flow • 1-21
Interstitial Pores • 2-56
Inter-Structural Voids • 2-56
Interval (Transect) • 1-4
Iron Depletions • 2-13
Irregular Pores • 2-56
Krotovinas • 2-61
Lamellae • 1-24, 2-22, 2-61
Lamina • 2-61
Landform • 1-4, 3-11
Landform Subset Lists • 3-10, 3-15
Landscape • 1-4, 3-11
Landuse • See Earth Cover - Kind
Limnic Materials • 1-24, 2-33
Lithic Contact • 1-24
Local Physiographic / Geographic Name • 3-8
Local Physiographic/Geographic Name • 1-4
Location • 1-2, 6-1
References • 6-5
Major Land Resource Area • 1-3
Mangans • 2-15, 2-24
Manner Of Failure • 2-49
Marl • 1-24, 2-33
Mass Movement Deposits • 1-16
Masses • 2-13, 2-17, 2-19
Master Horizons • 2-2, 4-1
Matrix Color • See Soil Matrix Color
Mean Sea Level • 1-4
Measurement Equivalents & Conversions • 7-2
Metamorphic Rocks • 1-18
Metric To English • 7-2
Microbiotic Crust • 2-61
Microfeature • 1-4
Microfeature Terms • 3-20
Microrelief • 1-8, 2-39, 3-26
Minimum Data Set • 2-67
USDA - NRCS
9-5
5/13/98
Miscellaneous • 7-1
Miscellaneous Field Notes • 2-67
MLRA • 1-3
Month / Day / Year • 1-1
Mottles • 2-9
Color • 2-11
Contrast • 2-11
Moisture State • 2-11
Quantity • 2-9
Shape • 2-11
Size • 2-9
Mountains (Geomorphic Components) • 1-8
Multicolored Pattern • 2-8
Name • 1-1
Nodules • 2-13, 2-17, 2-19
North American Geologic Time Scale • 5-7
Observation Method • 2-1
Kind • 2-1
Relative Size • 2-1
Odor • 2-67
Organic Deposits • 1-17
Organics • 1-19
Overland Flow • 1-21
Oxidation / Reduction • 2-13
Para (Soft) Rock Fragments • 2-32
Paralithic Contact • 1-24
Parent Material • 1-16
Particle Size Distribution • 2-28
Ped & Void Surface Features • 2-24
Amount • 2-26
Color • 2-27
Continuity • 2-26
Distinctness • 2-27
Kind • 2-24
Location • 2-27
Pendant • 2-23
5/13/98
9-6
USDA - NRCS
Penetration Resistance • 2-51
Penetration Resistance Class • 2-52
Perched Water Table • 1-13
Permeability • 2-63
Permeability (Discussion) • 2-62
Permeability Class • 2-63
Permeability Coefficient • 2-62
pH • 2-64
Physiographic Division • 1-4
Physiographic Divisions • 3-2
Physiographic Location • 1-4, 3-2
Physiographic Province • 1-4
Physiographic Provinces • 3-2
Physiographic Section • 1-4
Physiographic Sections • 3-2
Phytoliths • 2-19
Pipestems • 2-22
Plant Common Name • 1-15
Plant Opal • See Phytoliths
Plant Scientific Name • 1-15
Plant Symbol • 1-15
Plasticity • 2-50
Plasticity Class • 2-50
Plinthite • 1-24, 2-22
Pocket Penetrometer • 2-51
Ponding • 1-11
Depth • 1-11
Duration • 1-11
Frequency • 1-11
Pores • 2-56
Quantity • 2-53
Quantity Class • 2-53
Shape • 2-56
Size • 2-53
Size Classes • 2-55
Vertical Continuity • 2-58
Pores Discussion • 2-56
Precipitates • 1-19
Preferential Flow • 2-58
Pressure Faces • 2-24
Primary Packing Voids • 2-56
Profile / Pedon Description • 2-1
References • 2-68
Public Land Survey • 6-1
USDA - NRCS
9-7
5/13/98
Quadrangle Name • 1-2
Ranges (Location) • 6-1
Reaction (pH) • 2-64
Redox Concentrations • 2-13, 2-14
Redox Depletions • 2-13, 2-14
Redoximorphic Features • 2-14
Boundary • 2-16
Color • 2-16
Contrast • 2-16
Hardness • 2-16
Kind • 2-14
Location • 2-16
Moisture State • 2-16
Quantity • 2-15
Shape • 2-16
Size • 2-16
Redoximorphic Features (RMF) Discussion • 2-13
Reduced Conditions • 2-66
Reduced Matrix • 2-14
Reference Samples • 8-1
RMF Shapes • 2-22
Rock And Other Fragments • 2-35
Kind • 2-35
Roundness • 2-35
Size Classes And Descriptive Terms • 2-37
Volume Percent • 2-35
Rock Charts • 5-3
Rock Fragments • 2-32
Quantity • 2-32
Size • 2-32
Root Pseudomorphs • 2-22
Roots • 2-53
Location • 2-55
Quantity • 2-53
Quantity Class • 2-53
Size • 2-53
Size Classes • 2-55
Roundness • 2-35
Runoff • 1-21
5/13/98
9-8
USDA - NRCS
Rupture Resistance • 2-46
Blocks, Peds, And Clods • 2-47
Surface Crust And Plates • 2-48
Salinity • 2-66
Salinity Class • 2-66
Sand Coats • 2-24
Satiation • 1-12
Saturated Hydraulic Conductivity • 2-62, 2-63
Saturated Hydraulic Conductivity (Discussion) • 2-62
Saturation • 1-12
Scale • 1-2
Scientific Plant Name • 1-15
Seasonal High Water Table - Kind • 1-13
Secondary Carbonates • 1-24
Sections • 6-2
Sedimentary Rocks • 1-19
Series Name • 1-4
Shell Fragments • 2-19
Shot • 2-22
Silt Coats • 2-24
Site Description • 1-1
Skeletans • 2-24
Slickensides • 1-24, 2-24
Slope Aspect • 1-5, 3-22
Slope Complexity • 1-5, 3-22
Slope Gradient • 1-5, 3-22
Slope Shape • 1-6, 3-22
Smeariness • 2-49
Sodium Adsorption Ratio (SAR) • 2-66
Soft Powdery Lime • See Secondary Carbonates
Soft Rock Fragments • 2-32
Soil Color • 2-7
Soil Matrix Color • 2-7
Soil Moisture Status • See Soil Water State
Soil Permeability • 2-62
Soil Sample Kinds • 8-1
Soil Series Name • 1-4
Soil Structure • 2-38
Grade • 2-40
Size • 2-40
Type • 2-38
Soil Surface • 2-5
USDA - NRCS
9-9
5/13/98
Soil Survey Area Identification Number (SSID) • 1-2
Soil Taxonomy • 4-1
References • 4-9
Soil Temperature • 1-1
Soil Temperature Depth • 1-2
Soil Texture • 2-28
Soil Water State • 1-12
Special Features • 2-61
Sphericity • 2-36
State Abbreviation • 1-2
State Physiographic Area • 1-4, 3-8
State Plane Coordinate System • 6-4
Stickiness • 2-50
Stickiness Class • 2-50
Stone Line • 2-61
Stop Number (Transect) • 1-3
Stress Features • 2-24
Stringers • 2-22
Structure • See Soil Structure
Structure Shape • See Soil Structure - Type
Subordinate Distinctions • See Horizon Suffixes
Surface Coats • 2-15
Surface Crusts • 2-61
Surface Fragments • 1-22
Kind • 1-22
Mean Distance Between Fragments • 1-22
Surface Morphometry • 1-4, 3-22
Surface Runoff • 1-21
Surface Stoniness • 1-22
Table Comparing Particle Size Systems • 2-31
Taxonomic Classification • 2-2
Terms Used In Lieu Of Texture • 2-34
Terraces (Geomorphic Components) • 1-7
Texture • See Soil Texture
Texture Class • 2-28
Texture Modifiers • 2-29, 2-32
Texture Modifiers (Compositional) • 2-33
Threads • 2-22
Throughflow • 1-21
Till Terms • 5-8
Topographic Map • 1-2
Topographic Quadrangle • 1-2
5/13/98
9-10
USDA - NRCS
Townships (Location) • 6-1
Transect Delineation Size • 1-3
Transect Direction • 1-3
Transect ID • 1-3
Transect Kind • 1-3
Transect Selection Method • 1-3
Transect Stop Number • 1-3
Transects • 1-3
Trans-Horizon Cracks • 2-59
Transitional Horizons • 2-2, 4-1
Transported Deposits • 1-17
Tubular Pores • 2-56
Unconfined Compressive Strength • 2-51
Undulation • 2-6
Universal Transverse Mercator (UTM) Rectangular Coordinate System • 6-4
Variegated • 2-8
Vegetation / Land Cover • 1-14
Vesicular Pores • 2-56
Volcanic Deposits • 1-17
Volcaniclastic Terms • 5-9
Vughs • 2-56
Water Laid Deposits • 1-17
Water Status • 1-9
Water Table • See Depth To Water Table, Seasonal High Water Table
Wedge Structure • 2-39
USDA - NRCS
9-11
5/13/98